mesh-delivery-contracts: the build seats' part types Fetch, the toolchain, the artifacts, the check's levels and a step's result, and marks the times date-time; fixtures for a check ask and the three kinds of result (ADR 0634 §6; issue 1966)

Claude-Session: https://claude.ai/code/session_01NcbgfFSnn24M3GcqttoU7i

contracts/go/clients/containerimageregistryclient/reference/reference_test.go

@@ -7,7 +7,7 @@ import (
 
 var digest = "sha256:" + strings.Repeat("d", 64)
 
-var seats = Seats{Image: "container-image-registry", Object: "oci-artifact-registry"}
+var seats = Seats{Image: "container-image-registry", Object: "object-registry"}
 
 func TestAReferenceIsRecordedWithoutTheStoresAddress(t *testing.T) {
 	cases := map[string]string{
@@ -21,7 +21,7 @@ func TestAReferenceIsRecordedWithoutTheStoresAddress(t *testing.T) {
 		"https://registry.example/v2/gitea/config/blobs/" + digest: "https://registry.example/v2/gitea/config/blobs/" + digest,
 		// The form a registry seat answers is recorded as it is (ADR 0605 §9).
 		"container-image-registry/gitea/server@" + digest: "container-image-registry/gitea/server@" + digest,
-		"oci-artifact-registry/gitea/config@" + digest:    "oci-artifact-registry/gitea/config@" + digest,
+		"object-registry/gitea/config@" + digest:    "object-registry/gitea/config@" + digest,
 	}
 	for announced, want := range cases {
 		if got := seats.Recorded(announced); got != want {
@@ -33,7 +33,7 @@ func TestAReferenceIsRecordedWithoutTheStoresAddress(t *testing.T) {
 		ArtifactStoreScheme + "gitea/server@" + digest:       "10.0.0.1:5000/gitea/server@" + digest,
 		"container-image-registry/gitea/server@" + digest:    "10.0.0.1:5000/gitea/server@" + digest,
 		ArtifactStoreScheme + "gitea/config/blobs/" + digest: "http://10.0.0.1:5000/v2/gitea/config/blobs/" + digest,
-		"oci-artifact-registry/gitea/config@" + digest:       "http://10.0.0.1:5000/v2/gitea/config/blobs/" + digest,
+		"object-registry/gitea/config@" + digest:       "http://10.0.0.1:5000/v2/gitea/config/blobs/" + digest,
 		"registry.example/gitea/server@" + digest:            "registry.example/gitea/server@" + digest,
 		"mesh-artifact-store/gitea/server@" + digest:         "mesh-artifact-store/gitea/server@" + digest,
 		// An upstream copy under the holder's own naming, in both forms.
@@ -54,7 +54,7 @@ func TestAReferenceIsRecordedWithoutTheStoresAddress(t *testing.T) {
 	// The holder's naming of an upstream copy reads through the image seat only, and InUpstream reads its host and path.
 	for reference, want := range map[string]bool{
 		"container-image-registry/upstream/quay.io:443/org/app@" + digest: true,
-		"oci-artifact-registry/upstream/quay.io:443/org/app@" + digest:    false,
+		"object-registry/upstream/quay.io:443/org/app@" + digest:    false,
 		"container-image-registry/upstream/org/app@" + digest:             false,
 		"container-image-registry/upstream/quay.io/app":                   false,
 	} {

contracts/go/seats/nodebuildgo/contract.go

@@ -187,26 +187,27 @@ func DecodeToolchainsByNodeLanguageValue(raw []byte) (ToolchainsByNodeLanguageVa
 	return v, nil
 }
 
-// BuildAnswerArtifactsItem is a type of the contract.
+// AskArtifact is one artifact of a build ask: built from the fetched tree, or copied from an upstream pin.
-type BuildAnswerArtifactsItem struct {
+type AskArtifact struct {
-	Artifact  string `json:"artifact"`
+	Artifact string `json:"artifact"`
-	Digest    string `json:"digest"`
+	From     string `json:"from,omitempty"`
-	Reference string `json:"reference,omitempty"`
+	Seat     string `json:"seat,omitempty"`
-}
+	Version  string `json:"version,omitempty"`
-
-// BuildAnswerToolchain is a type of the contract.
-type BuildAnswerToolchain struct {
-	Language string `json:"language"`
-	Recipe   string `json:"recipe"`
-	Version  string `json:"version"`
 }
 
 // BuildAnswer is a type of the contract.
 type BuildAnswer struct {
-	Artifacts []BuildAnswerArtifactsItem `json:"artifacts"`
+	Artifacts []BuiltArtifact `json:"artifacts"`
-	Imports   []string                   `json:"imports,omitempty"`
+	Imports   []string        `json:"imports,omitempty"`
-	OutOfStep []string                   `json:"out-of-step,omitempty"`
+	OutOfStep []string        `json:"out-of-step,omitempty"`
-	Toolchain *BuildAnswerToolchain      `json:"toolchain,omitempty"`
+	Toolchain *ToolchainUsed  `json:"toolchain,omitempty"`
+}
+
+// BuiltArtifact is one artifact a build made: its digest and the reference it was published under.
+type BuiltArtifact struct {
+	Artifact  string `json:"artifact"`
+	Digest    string `json:"digest"`
+	Reference string `json:"reference,omitempty"`
 }
 
 // Capacity is how many steps the node runs at once.
@@ -229,56 +230,10 @@ type Capacity struct {
 	Why string `json:"why"`
 }
 
-// CheckAnswerLevelsItemDigestNeedsItem is a type of the contract.
-type CheckAnswerLevelsItemDigestNeedsItem struct {
-	Needs   []string `json:"needs,omitempty"`
-	Package string   `json:"package,omitempty"`
-}
-
-// CheckAnswerLevelsItemDigestPackagesItem is a type of the contract.
-type CheckAnswerLevelsItemDigestPackagesItem struct {
-	Digest  string `json:"digest"`
-	Package string `json:"package"`
-}
-
-// CheckAnswerLevelsItemDigest is a type of the contract.
-type CheckAnswerLevelsItemDigest struct {
-	Beside       []string                                  `json:"beside,omitempty"`
-	JudgedBy     string                                    `json:"judged_by,omitempty"`
-	Level        string                                    `json:"level,omitempty"`
-	Needs        []CheckAnswerLevelsItemDigestNeedsItem    `json:"needs,omitempty"`
-	Packages     []CheckAnswerLevelsItemDigestPackagesItem `json:"packages,omitempty"`
-	WithoutTests []string                                  `json:"without_tests,omitempty"`
-}
-
-// CheckAnswerLevelsItemKeptItem is a type of the contract.
-type CheckAnswerLevelsItemKeptItem struct {
-	Digest  string `json:"digest,omitempty"`
-	Package string `json:"package,omitempty"`
-	Tests   int64  `json:"tests,omitempty"`
-}
-
-// CheckAnswerLevelsItemUnmetItem is a type of the contract.
-type CheckAnswerLevelsItemUnmetItem struct {
-	Needs   []string `json:"needs,omitempty"`
-	Package string   `json:"package,omitempty"`
-}
-
-// CheckAnswerLevelsItem is a type of the contract.
-type CheckAnswerLevelsItem struct {
-	Digest *CheckAnswerLevelsItemDigest     `json:"digest,omitempty"`
-	Judged string                           `json:"judged,omitempty"`
-	Kept   []CheckAnswerLevelsItemKeptItem  `json:"kept,omitempty"`
-	Level  string                           `json:"level"`
-	Tests  []any                            `json:"tests,omitempty"`
-	Unmet  []CheckAnswerLevelsItemUnmetItem `json:"unmet,omitempty"`
-}
-
 // CheckAnswer is a type of the contract.
 type CheckAnswer struct {
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch  Fetch         `json:"fetch"`
-	Fetch  any                     `json:"fetch"`
+	Levels []LevelAnswer `json:"levels,omitempty"`
-	Levels []CheckAnswerLevelsItem `json:"levels,omitempty"`
 }
 
 // ComposeAnswer is a type of the contract.
@@ -289,6 +244,77 @@ type ComposeAnswer struct {
 	Verdict any `json:"verdict,omitempty"`
 }
 
+// FetchBesideItem is a type of the contract.
+type FetchBesideItem struct {
+	Commit     string `json:"commit"`
+	Repository string `json:"repository"`
+}
+
+// Fetch is what a build module's fetch tool is asked: the repository and the full commit, the pull request's ref when only its head carries the commit, the trunk commit to merge onto for a merge preview, the module's directory and named paths, the mesh packages to build against, and the sibling repositories placed beside.
+type Fetch struct {
+	// the trunk commit a merge preview merges onto
+	Base string `json:"base,omitempty"`
+	// the sibling repositories placed beside the fetched tree
+	Beside []FetchBesideItem `json:"beside,omitempty"`
+	// the full commit
+	Commit string `json:"commit"`
+	// the module's directory in the repository ("." for its root), with paths
+	Dir string `json:"dir,omitempty"`
+	// the version (a full commit) of each mesh package to build against, by its module path
+	Packages map[string]string `json:"packages,omitempty"`
+	// the paths the module names, relative to dir
+	Paths []string `json:"paths,omitempty"`
+	// the pull request's ref, when only its head carries the commit
+	Ref string `json:"ref,omitempty"`
+	// <owner>/<name>
+	Repository string `json:"repository"`
+}
+
+// LevelAnswerDigestNeedsItem is a type of the contract.
+type LevelAnswerDigestNeedsItem struct {
+	Needs   []string `json:"needs,omitempty"`
+	Package string   `json:"package,omitempty"`
+}
+
+// LevelAnswerDigestPackagesItem is a type of the contract.
+type LevelAnswerDigestPackagesItem struct {
+	Digest  string `json:"digest"`
+	Package string `json:"package"`
+}
+
+// LevelAnswerDigest is a type of the contract.
+type LevelAnswerDigest struct {
+	Beside       []string                        `json:"beside,omitempty"`
+	JudgedBy     string                          `json:"judged_by,omitempty"`
+	Level        string                          `json:"level,omitempty"`
+	Needs        []LevelAnswerDigestNeedsItem    `json:"needs,omitempty"`
+	Packages     []LevelAnswerDigestPackagesItem `json:"packages,omitempty"`
+	WithoutTests []string                        `json:"without_tests,omitempty"`
+}
+
+// LevelAnswerKeptItem is a type of the contract.
+type LevelAnswerKeptItem struct {
+	Digest  string `json:"digest,omitempty"`
+	Package string `json:"package,omitempty"`
+	Tests   int64  `json:"tests,omitempty"`
+}
+
+// LevelAnswerUnmetItem is a type of the contract.
+type LevelAnswerUnmetItem struct {
+	Needs   []string `json:"needs,omitempty"`
+	Package string   `json:"package,omitempty"`
+}
+
+// LevelAnswer is one level of a check ask: the digest's answer, the kept verdicts taken, one test result per test step run, and the packages the node could not test.
+type LevelAnswer struct {
+	Digest *LevelAnswerDigest     `json:"digest,omitempty"`
+	Judged string                 `json:"judged,omitempty"`
+	Kept   []LevelAnswerKeptItem  `json:"kept,omitempty"`
+	Level  string                 `json:"level"`
+	Tests  []any                  `json:"tests,omitempty"`
+	Unmet  []LevelAnswerUnmetItem `json:"unmet,omitempty"`
+}
+
 // Pause is whether the node takes no new ask.
 type Pause struct {
 	// when (RFC 3339 time)
@@ -308,10 +334,9 @@ type Step struct {
 	Owner string `json:"owner,omitempty"`
 	Phase string `json:"phase,omitempty"`
 	// when (RFC 3339 time)
-	PhaseAt string `json:"phase-at,omitempty"`
+	PhaseAt string      `json:"phase-at,omitempty"`
-	Reason  string `json:"reason,omitempty"`
+	Reason  string      `json:"reason,omitempty"`
-	// what the step answered
+	Result  *StepResult `json:"result,omitempty"`
-	Result any `json:"result,omitempty"`
 	// when (RFC 3339 time)
 	Started string `json:"started"`
 	// running, passed, failed or refused
@@ -322,37 +347,20 @@ type Step struct {
 	What string `json:"what,omitempty"`
 }
 
-// StepAskBuildArtifactsItem is a type of the contract.
-type StepAskBuildArtifactsItem struct {
-	Artifact string `json:"artifact"`
-	From     string `json:"from,omitempty"`
-	Seat     string `json:"seat,omitempty"`
-	Version  string `json:"version,omitempty"`
-}
-
-// StepAskBuildToolchain is a type of the contract.
-type StepAskBuildToolchain struct {
-	Language string `json:"language"`
-	Recipe   string `json:"recipe"`
-	Version  string `json:"version"`
-}
-
 // StepAskBuild is a type of the contract.
 type StepAskBuild struct {
-	Artifacts []StepAskBuildArtifactsItem `json:"artifacts"`
+	Artifacts []AskArtifact  `json:"artifacts"`
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch     *Fetch         `json:"fetch,omitempty"`
-	Fetch     any                    `json:"fetch,omitempty"`
+	Fp        string         `json:"fp,omitempty"`
-	Fp        string                 `json:"fp,omitempty"`
+	Module    string         `json:"module"`
-	Module    string                 `json:"module"`
+	Path      string         `json:"path,omitempty"`
-	Path      string                 `json:"path,omitempty"`
+	Publish   bool           `json:"publish,omitempty"`
-	Publish   bool                   `json:"publish,omitempty"`
+	Toolchain *ToolchainUsed `json:"toolchain,omitempty"`
-	Toolchain *StepAskBuildToolchain `json:"toolchain,omitempty"`
 }
 
 // StepAskCheck is a type of the contract.
 type StepAskCheck struct {
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch      Fetch    `json:"fetch"`
-	Fetch      any      `json:"fetch"`
 	Kept       bool     `json:"kept,omitempty"`
 	Levels     []string `json:"levels"`
 	Packages   []string `json:"packages,omitempty"`
@@ -363,9 +371,8 @@ type StepAskCheck struct {
 
 // StepAskCompose is a type of the contract.
 type StepAskCompose struct {
-	Dir string `json:"dir"`
+	Dir     string `json:"dir"`
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch   Fetch  `json:"fetch"`
-	Fetch   any    `json:"fetch"`
 	Package string `json:"package"`
 	Reader  string `json:"reader,omitempty"`
 	// the compose-candidate request
@@ -392,6 +399,26 @@ type StepAsk struct {
 	V int64 `json:"v,omitempty"`
 }
 
+// StepResult is what a step answered, by the kind of ask: a build's artifacts, toolchain, imports and out-of-step modules; a check's fetch and levels; a compose's built, key and verdict; a declined ask's declined, needs and lacks. The fields of the kinds do not meet, so one layout holds the four.
+type StepResult struct {
+	Artifacts []BuiltArtifact `json:"artifacts,omitempty"`
+	Built     bool            `json:"built,omitempty"`
+	// the holder declined the ask: its node lacks what the ask needs
+	Declined bool     `json:"declined,omitempty"`
+	Fetch    *Fetch   `json:"fetch,omitempty"`
+	Imports  []string `json:"imports,omitempty"`
+	Key      string   `json:"key,omitempty"`
+	// what the holder's node lacks of it
+	Lacks  []string      `json:"lacks,omitempty"`
+	Levels []LevelAnswer `json:"levels,omitempty"`
+	// what the declined ask needs
+	Needs     []string       `json:"needs,omitempty"`
+	OutOfStep []string       `json:"out-of-step,omitempty"`
+	Toolchain *ToolchainUsed `json:"toolchain,omitempty"`
+	// the compose-candidate verdict (the composer's own layout)
+	Verdict any `json:"verdict,omitempty"`
+}
+
 // Toolchain is the toolchain a node reports.
 type Toolchain struct {
 	// when (RFC 3339 time)
@@ -404,6 +431,13 @@ type Toolchain struct {
 	Version string `json:"version"`
 }
 
+// ToolchainUsed is the toolchain a build was made with: the language, the installed version and the build module's recipe.
+type ToolchainUsed struct {
+	Language string `json:"language"`
+	Recipe   string `json:"recipe"`
+	Version  string `json:"version"`
+}
+
 // CurrentInput is what current takes.
 type CurrentInput struct {
 }

contracts/go/seats/nodebuildgo/contract_test.go

@@ -39,6 +39,14 @@ func TestFixtures(t *testing.T) {
 			}, subjectIs: nil},
 		{name: "a build ask", subject: "mesh.seat.node-build-go.accept.delivery", given: "{\"asker\":\"mesh-delivery-builder\",\"build\":{\"artifacts\":[{\"artifact\":\"go\"}],\"module\":\"nats\"},\"id\":\"a1b2\",\"kind\":\"build\",\"language\":\"go\"}", wire: "{\"asker\":\"mesh-delivery-builder\",\"build\":{\"artifacts\":[{\"artifact\":\"go\"}],\"module\":\"nats\"},\"id\":\"a1b2\",\"kind\":\"build\",\"language\":\"go\"}",
 			decode: func(b []byte) (any, error) { var v DeliveryAccept; err := json.Unmarshal(b, &v); return v, err }, subjectIs: regexp.MustCompile("^mesh\\.seat\\.node-build-go\\.accept\\.delivery$")},
+		{name: "a check ask with its fetch, siblings and levels", subject: "mesh.seat.node-build-go.accept.check", given: "{\"asker\":\"mesh-delivery-checker\",\"at\":\"2026-11-05T10:00:00Z\",\"check\":{\"fetch\":{\"base\":\"89abcdef0123456789abcdef0123456789abcdef\",\"beside\":[{\"commit\":\"fedcba9876543210fedcba9876543210fedcba98\",\"repository\":\"novox/mesh-sdk\"}],\"commit\":\"0123456789abcdef0123456789abcdef01234567\",\"packages\":{\"git.novox.be/novox/mesh-sdk/go\":\"fedcba9876543210fedcba9876543210fedcba98\"},\"ref\":\"refs/pull/7/head\",\"repository\":\"novox/mesh-catalog\"},\"kept\":true,\"levels\":[\"unit\",\"integration\"]},\"id\":\"c3d4\",\"kind\":\"check\",\"language\":\"go\",\"v\":1}", wire: "{\"asker\":\"mesh-delivery-checker\",\"at\":\"2026-11-05T10:00:00Z\",\"check\":{\"fetch\":{\"base\":\"89abcdef0123456789abcdef0123456789abcdef\",\"beside\":[{\"commit\":\"fedcba9876543210fedcba9876543210fedcba98\",\"repository\":\"novox/mesh-sdk\"}],\"commit\":\"0123456789abcdef0123456789abcdef01234567\",\"packages\":{\"git.novox.be/novox/mesh-sdk/go\":\"fedcba9876543210fedcba9876543210fedcba98\"},\"ref\":\"refs/pull/7/head\",\"repository\":\"novox/mesh-catalog\"},\"kept\":true,\"levels\":[\"unit\",\"integration\"]},\"id\":\"c3d4\",\"kind\":\"check\",\"language\":\"go\",\"v\":1}",
+			decode: func(b []byte) (any, error) { var v CheckAccept; err := json.Unmarshal(b, &v); return v, err }, subjectIs: regexp.MustCompile("^mesh\\.seat\\.node-build-go\\.accept\\.check$")},
+		{name: "a finished build step with its artifacts", subject: "", given: "{\"ended\":\"2026-11-05T10:03:00Z\",\"id\":\"a1b2\",\"node\":\"ace\",\"result\":{\"artifacts\":[{\"artifact\":\"go\",\"digest\":\"sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\"reference\":\"container-image-registry/nats/go@sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\"}],\"imports\":[\"git.novox.be/novox/mesh-sdk/go\"],\"toolchain\":{\"language\":\"go\",\"recipe\":\"1\",\"version\":\"1.26.0\"}},\"started\":\"2026-11-05T10:00:00Z\",\"state\":\"passed\",\"tool\":\"build\",\"v\":1}", wire: "{\"ended\":\"2026-11-05T10:03:00Z\",\"id\":\"a1b2\",\"node\":\"ace\",\"result\":{\"artifacts\":[{\"artifact\":\"go\",\"digest\":\"sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\",\"reference\":\"container-image-registry/nats/go@sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\"}],\"imports\":[\"git.novox.be/novox/mesh-sdk/go\"],\"toolchain\":{\"language\":\"go\",\"recipe\":\"1\",\"version\":\"1.26.0\"}},\"started\":\"2026-11-05T10:00:00Z\",\"state\":\"passed\",\"tool\":\"build\",\"v\":1}",
+			decode: func(b []byte) (any, error) { var v StepsByNodeIDValue; err := json.Unmarshal(b, &v); return v, err }, subjectIs: nil},
+		{name: "a finished check step with its levels", subject: "", given: "{\"ended\":\"2026-11-05T10:06:00Z\",\"id\":\"c3d4\",\"node\":\"ace\",\"result\":{\"fetch\":{\"commit\":\"0123456789abcdef0123456789abcdef01234567\",\"repository\":\"novox/mesh-catalog\"},\"levels\":[{\"digest\":{\"level\":\"unit\",\"packages\":[{\"digest\":\"sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\",\"package\":\"./modules/a\"}]},\"kept\":[{\"digest\":\"sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\",\"package\":\"./modules/a\",\"tests\":12}],\"level\":\"unit\",\"tests\":[{\"package\":\"./modules/b\",\"pass\":true}],\"unmet\":[{\"needs\":[\"docker\"],\"package\":\"./modules/c\"}]}]},\"started\":\"2026-11-05T10:00:00Z\",\"state\":\"passed\",\"tool\":\"check\",\"v\":1}", wire: "{\"ended\":\"2026-11-05T10:06:00Z\",\"id\":\"c3d4\",\"node\":\"ace\",\"result\":{\"fetch\":{\"commit\":\"0123456789abcdef0123456789abcdef01234567\",\"repository\":\"novox/mesh-catalog\"},\"levels\":[{\"digest\":{\"level\":\"unit\",\"packages\":[{\"digest\":\"sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\",\"package\":\"./modules/a\"}]},\"kept\":[{\"digest\":\"sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb\",\"package\":\"./modules/a\",\"tests\":12}],\"level\":\"unit\",\"tests\":[{\"package\":\"./modules/b\",\"pass\":true}],\"unmet\":[{\"needs\":[\"docker\"],\"package\":\"./modules/c\"}]}]},\"started\":\"2026-11-05T10:00:00Z\",\"state\":\"passed\",\"tool\":\"check\",\"v\":1}",
+			decode: func(b []byte) (any, error) { var v StepsByNodeIDValue; err := json.Unmarshal(b, &v); return v, err }, subjectIs: nil},
+		{name: "a declined step", subject: "", given: "{\"id\":\"c3d5\",\"node\":\"ace\",\"result\":{\"declined\":true,\"lacks\":[\"docker\"],\"needs\":[\"docker\"]},\"started\":\"2026-11-05T10:00:00Z\",\"state\":\"refused\",\"tool\":\"check\",\"v\":1}", wire: "{\"id\":\"c3d5\",\"node\":\"ace\",\"result\":{\"declined\":true,\"lacks\":[\"docker\"],\"needs\":[\"docker\"]},\"started\":\"2026-11-05T10:00:00Z\",\"state\":\"refused\",\"tool\":\"check\",\"v\":1}",
+			decode: func(b []byte) (any, error) { var v StepsByNodeIDValue; err := json.Unmarshal(b, &v); return v, err }, subjectIs: nil},
 	}
 	for _, c := range cases {
 		v, err := c.decode([]byte(c.given))

contracts/go/seats/nodebuildimage/contract.go

@@ -187,26 +187,27 @@ func DecodeToolchainsByNodeLanguageValue(raw []byte) (ToolchainsByNodeLanguageVa
 	return v, nil
 }
 
-// BuildAnswerArtifactsItem is a type of the contract.
+// AskArtifact is one artifact of a build ask: built from the fetched tree, or copied from an upstream pin.
-type BuildAnswerArtifactsItem struct {
+type AskArtifact struct {
-	Artifact  string `json:"artifact"`
+	Artifact string `json:"artifact"`
-	Digest    string `json:"digest"`
+	From     string `json:"from,omitempty"`
-	Reference string `json:"reference,omitempty"`
+	Seat     string `json:"seat,omitempty"`
-}
+	Version  string `json:"version,omitempty"`
-
-// BuildAnswerToolchain is a type of the contract.
-type BuildAnswerToolchain struct {
-	Language string `json:"language"`
-	Recipe   string `json:"recipe"`
-	Version  string `json:"version"`
 }
 
 // BuildAnswer is a type of the contract.
 type BuildAnswer struct {
-	Artifacts []BuildAnswerArtifactsItem `json:"artifacts"`
+	Artifacts []BuiltArtifact `json:"artifacts"`
-	Imports   []string                   `json:"imports,omitempty"`
+	Imports   []string        `json:"imports,omitempty"`
-	OutOfStep []string                   `json:"out-of-step,omitempty"`
+	OutOfStep []string        `json:"out-of-step,omitempty"`
-	Toolchain *BuildAnswerToolchain      `json:"toolchain,omitempty"`
+	Toolchain *ToolchainUsed  `json:"toolchain,omitempty"`
+}
+
+// BuiltArtifact is one artifact a build made: its digest and the reference it was published under.
+type BuiltArtifact struct {
+	Artifact  string `json:"artifact"`
+	Digest    string `json:"digest"`
+	Reference string `json:"reference,omitempty"`
 }
 
 // Capacity is how many steps the node runs at once.
@@ -229,56 +230,10 @@ type Capacity struct {
 	Why string `json:"why"`
 }
 
-// CheckAnswerLevelsItemDigestNeedsItem is a type of the contract.
-type CheckAnswerLevelsItemDigestNeedsItem struct {
-	Needs   []string `json:"needs,omitempty"`
-	Package string   `json:"package,omitempty"`
-}
-
-// CheckAnswerLevelsItemDigestPackagesItem is a type of the contract.
-type CheckAnswerLevelsItemDigestPackagesItem struct {
-	Digest  string `json:"digest"`
-	Package string `json:"package"`
-}
-
-// CheckAnswerLevelsItemDigest is a type of the contract.
-type CheckAnswerLevelsItemDigest struct {
-	Beside       []string                                  `json:"beside,omitempty"`
-	JudgedBy     string                                    `json:"judged_by,omitempty"`
-	Level        string                                    `json:"level,omitempty"`
-	Needs        []CheckAnswerLevelsItemDigestNeedsItem    `json:"needs,omitempty"`
-	Packages     []CheckAnswerLevelsItemDigestPackagesItem `json:"packages,omitempty"`
-	WithoutTests []string                                  `json:"without_tests,omitempty"`
-}
-
-// CheckAnswerLevelsItemKeptItem is a type of the contract.
-type CheckAnswerLevelsItemKeptItem struct {
-	Digest  string `json:"digest,omitempty"`
-	Package string `json:"package,omitempty"`
-	Tests   int64  `json:"tests,omitempty"`
-}
-
-// CheckAnswerLevelsItemUnmetItem is a type of the contract.
-type CheckAnswerLevelsItemUnmetItem struct {
-	Needs   []string `json:"needs,omitempty"`
-	Package string   `json:"package,omitempty"`
-}
-
-// CheckAnswerLevelsItem is a type of the contract.
-type CheckAnswerLevelsItem struct {
-	Digest *CheckAnswerLevelsItemDigest     `json:"digest,omitempty"`
-	Judged string                           `json:"judged,omitempty"`
-	Kept   []CheckAnswerLevelsItemKeptItem  `json:"kept,omitempty"`
-	Level  string                           `json:"level"`
-	Tests  []any                            `json:"tests,omitempty"`
-	Unmet  []CheckAnswerLevelsItemUnmetItem `json:"unmet,omitempty"`
-}
-
 // CheckAnswer is a type of the contract.
 type CheckAnswer struct {
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch  Fetch         `json:"fetch"`
-	Fetch  any                     `json:"fetch"`
+	Levels []LevelAnswer `json:"levels,omitempty"`
-	Levels []CheckAnswerLevelsItem `json:"levels,omitempty"`
 }
 
 // ComposeAnswer is a type of the contract.
@@ -289,6 +244,77 @@ type ComposeAnswer struct {
 	Verdict any `json:"verdict,omitempty"`
 }
 
+// FetchBesideItem is a type of the contract.
+type FetchBesideItem struct {
+	Commit     string `json:"commit"`
+	Repository string `json:"repository"`
+}
+
+// Fetch is what a build module's fetch tool is asked: the repository and the full commit, the pull request's ref when only its head carries the commit, the trunk commit to merge onto for a merge preview, the module's directory and named paths, the mesh packages to build against, and the sibling repositories placed beside.
+type Fetch struct {
+	// the trunk commit a merge preview merges onto
+	Base string `json:"base,omitempty"`
+	// the sibling repositories placed beside the fetched tree
+	Beside []FetchBesideItem `json:"beside,omitempty"`
+	// the full commit
+	Commit string `json:"commit"`
+	// the module's directory in the repository ("." for its root), with paths
+	Dir string `json:"dir,omitempty"`
+	// the version (a full commit) of each mesh package to build against, by its module path
+	Packages map[string]string `json:"packages,omitempty"`
+	// the paths the module names, relative to dir
+	Paths []string `json:"paths,omitempty"`
+	// the pull request's ref, when only its head carries the commit
+	Ref string `json:"ref,omitempty"`
+	// <owner>/<name>
+	Repository string `json:"repository"`
+}
+
+// LevelAnswerDigestNeedsItem is a type of the contract.
+type LevelAnswerDigestNeedsItem struct {
+	Needs   []string `json:"needs,omitempty"`
+	Package string   `json:"package,omitempty"`
+}
+
+// LevelAnswerDigestPackagesItem is a type of the contract.
+type LevelAnswerDigestPackagesItem struct {
+	Digest  string `json:"digest"`
+	Package string `json:"package"`
+}
+
+// LevelAnswerDigest is a type of the contract.
+type LevelAnswerDigest struct {
+	Beside       []string                        `json:"beside,omitempty"`
+	JudgedBy     string                          `json:"judged_by,omitempty"`
+	Level        string                          `json:"level,omitempty"`
+	Needs        []LevelAnswerDigestNeedsItem    `json:"needs,omitempty"`
+	Packages     []LevelAnswerDigestPackagesItem `json:"packages,omitempty"`
+	WithoutTests []string                        `json:"without_tests,omitempty"`
+}
+
+// LevelAnswerKeptItem is a type of the contract.
+type LevelAnswerKeptItem struct {
+	Digest  string `json:"digest,omitempty"`
+	Package string `json:"package,omitempty"`
+	Tests   int64  `json:"tests,omitempty"`
+}
+
+// LevelAnswerUnmetItem is a type of the contract.
+type LevelAnswerUnmetItem struct {
+	Needs   []string `json:"needs,omitempty"`
+	Package string   `json:"package,omitempty"`
+}
+
+// LevelAnswer is one level of a check ask: the digest's answer, the kept verdicts taken, one test result per test step run, and the packages the node could not test.
+type LevelAnswer struct {
+	Digest *LevelAnswerDigest     `json:"digest,omitempty"`
+	Judged string                 `json:"judged,omitempty"`
+	Kept   []LevelAnswerKeptItem  `json:"kept,omitempty"`
+	Level  string                 `json:"level"`
+	Tests  []any                  `json:"tests,omitempty"`
+	Unmet  []LevelAnswerUnmetItem `json:"unmet,omitempty"`
+}
+
 // Pause is whether the node takes no new ask.
 type Pause struct {
 	// when (RFC 3339 time)
@@ -308,10 +334,9 @@ type Step struct {
 	Owner string `json:"owner,omitempty"`
 	Phase string `json:"phase,omitempty"`
 	// when (RFC 3339 time)
-	PhaseAt string `json:"phase-at,omitempty"`
+	PhaseAt string      `json:"phase-at,omitempty"`
-	Reason  string `json:"reason,omitempty"`
+	Reason  string      `json:"reason,omitempty"`
-	// what the step answered
+	Result  *StepResult `json:"result,omitempty"`
-	Result any `json:"result,omitempty"`
 	// when (RFC 3339 time)
 	Started string `json:"started"`
 	// running, passed, failed or refused
@@ -322,37 +347,20 @@ type Step struct {
 	What string `json:"what,omitempty"`
 }
 
-// StepAskBuildArtifactsItem is a type of the contract.
-type StepAskBuildArtifactsItem struct {
-	Artifact string `json:"artifact"`
-	From     string `json:"from,omitempty"`
-	Seat     string `json:"seat,omitempty"`
-	Version  string `json:"version,omitempty"`
-}
-
-// StepAskBuildToolchain is a type of the contract.
-type StepAskBuildToolchain struct {
-	Language string `json:"language"`
-	Recipe   string `json:"recipe"`
-	Version  string `json:"version"`
-}
-
 // StepAskBuild is a type of the contract.
 type StepAskBuild struct {
-	Artifacts []StepAskBuildArtifactsItem `json:"artifacts"`
+	Artifacts []AskArtifact  `json:"artifacts"`
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch     *Fetch         `json:"fetch,omitempty"`
-	Fetch     any                    `json:"fetch,omitempty"`
+	Fp        string         `json:"fp,omitempty"`
-	Fp        string                 `json:"fp,omitempty"`
+	Module    string         `json:"module"`
-	Module    string                 `json:"module"`
+	Path      string         `json:"path,omitempty"`
-	Path      string                 `json:"path,omitempty"`
+	Publish   bool           `json:"publish,omitempty"`
-	Publish   bool                   `json:"publish,omitempty"`
+	Toolchain *ToolchainUsed `json:"toolchain,omitempty"`
-	Toolchain *StepAskBuildToolchain `json:"toolchain,omitempty"`
 }
 
 // StepAskCheck is a type of the contract.
 type StepAskCheck struct {
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch      Fetch    `json:"fetch"`
-	Fetch      any      `json:"fetch"`
 	Kept       bool     `json:"kept,omitempty"`
 	Levels     []string `json:"levels"`
 	Packages   []string `json:"packages,omitempty"`
@@ -363,9 +371,8 @@ type StepAskCheck struct {
 
 // StepAskCompose is a type of the contract.
 type StepAskCompose struct {
-	Dir string `json:"dir"`
+	Dir     string `json:"dir"`
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch   Fetch  `json:"fetch"`
-	Fetch   any    `json:"fetch"`
 	Package string `json:"package"`
 	Reader  string `json:"reader,omitempty"`
 	// the compose-candidate request
@@ -392,6 +399,26 @@ type StepAsk struct {
 	V int64 `json:"v,omitempty"`
 }
 
+// StepResult is what a step answered, by the kind of ask: a build's artifacts, toolchain, imports and out-of-step modules; a check's fetch and levels; a compose's built, key and verdict; a declined ask's declined, needs and lacks. The fields of the kinds do not meet, so one layout holds the four.
+type StepResult struct {
+	Artifacts []BuiltArtifact `json:"artifacts,omitempty"`
+	Built     bool            `json:"built,omitempty"`
+	// the holder declined the ask: its node lacks what the ask needs
+	Declined bool     `json:"declined,omitempty"`
+	Fetch    *Fetch   `json:"fetch,omitempty"`
+	Imports  []string `json:"imports,omitempty"`
+	Key      string   `json:"key,omitempty"`
+	// what the holder's node lacks of it
+	Lacks  []string      `json:"lacks,omitempty"`
+	Levels []LevelAnswer `json:"levels,omitempty"`
+	// what the declined ask needs
+	Needs     []string       `json:"needs,omitempty"`
+	OutOfStep []string       `json:"out-of-step,omitempty"`
+	Toolchain *ToolchainUsed `json:"toolchain,omitempty"`
+	// the compose-candidate verdict (the composer's own layout)
+	Verdict any `json:"verdict,omitempty"`
+}
+
 // Toolchain is the toolchain a node reports.
 type Toolchain struct {
 	// when (RFC 3339 time)
@@ -404,6 +431,13 @@ type Toolchain struct {
 	Version string `json:"version"`
 }
 
+// ToolchainUsed is the toolchain a build was made with: the language, the installed version and the build module's recipe.
+type ToolchainUsed struct {
+	Language string `json:"language"`
+	Recipe   string `json:"recipe"`
+	Version  string `json:"version"`
+}
+
 // CurrentInput is what current takes.
 type CurrentInput struct {
 }

contracts/go/seats/nodebuildnode/contract.go

@@ -187,26 +187,27 @@ func DecodeToolchainsByNodeLanguageValue(raw []byte) (ToolchainsByNodeLanguageVa
 	return v, nil
 }
 
-// BuildAnswerArtifactsItem is a type of the contract.
+// AskArtifact is one artifact of a build ask: built from the fetched tree, or copied from an upstream pin.
-type BuildAnswerArtifactsItem struct {
+type AskArtifact struct {
-	Artifact  string `json:"artifact"`
+	Artifact string `json:"artifact"`
-	Digest    string `json:"digest"`
+	From     string `json:"from,omitempty"`
-	Reference string `json:"reference,omitempty"`
+	Seat     string `json:"seat,omitempty"`
-}
+	Version  string `json:"version,omitempty"`
-
-// BuildAnswerToolchain is a type of the contract.
-type BuildAnswerToolchain struct {
-	Language string `json:"language"`
-	Recipe   string `json:"recipe"`
-	Version  string `json:"version"`
 }
 
 // BuildAnswer is a type of the contract.
 type BuildAnswer struct {
-	Artifacts []BuildAnswerArtifactsItem `json:"artifacts"`
+	Artifacts []BuiltArtifact `json:"artifacts"`
-	Imports   []string                   `json:"imports,omitempty"`
+	Imports   []string        `json:"imports,omitempty"`
-	OutOfStep []string                   `json:"out-of-step,omitempty"`
+	OutOfStep []string        `json:"out-of-step,omitempty"`
-	Toolchain *BuildAnswerToolchain      `json:"toolchain,omitempty"`
+	Toolchain *ToolchainUsed  `json:"toolchain,omitempty"`
+}
+
+// BuiltArtifact is one artifact a build made: its digest and the reference it was published under.
+type BuiltArtifact struct {
+	Artifact  string `json:"artifact"`
+	Digest    string `json:"digest"`
+	Reference string `json:"reference,omitempty"`
 }
 
 // Capacity is how many steps the node runs at once.
@@ -229,56 +230,10 @@ type Capacity struct {
 	Why string `json:"why"`
 }
 
-// CheckAnswerLevelsItemDigestNeedsItem is a type of the contract.
-type CheckAnswerLevelsItemDigestNeedsItem struct {
-	Needs   []string `json:"needs,omitempty"`
-	Package string   `json:"package,omitempty"`
-}
-
-// CheckAnswerLevelsItemDigestPackagesItem is a type of the contract.
-type CheckAnswerLevelsItemDigestPackagesItem struct {
-	Digest  string `json:"digest"`
-	Package string `json:"package"`
-}
-
-// CheckAnswerLevelsItemDigest is a type of the contract.
-type CheckAnswerLevelsItemDigest struct {
-	Beside       []string                                  `json:"beside,omitempty"`
-	JudgedBy     string                                    `json:"judged_by,omitempty"`
-	Level        string                                    `json:"level,omitempty"`
-	Needs        []CheckAnswerLevelsItemDigestNeedsItem    `json:"needs,omitempty"`
-	Packages     []CheckAnswerLevelsItemDigestPackagesItem `json:"packages,omitempty"`
-	WithoutTests []string                                  `json:"without_tests,omitempty"`
-}
-
-// CheckAnswerLevelsItemKeptItem is a type of the contract.
-type CheckAnswerLevelsItemKeptItem struct {
-	Digest  string `json:"digest,omitempty"`
-	Package string `json:"package,omitempty"`
-	Tests   int64  `json:"tests,omitempty"`
-}
-
-// CheckAnswerLevelsItemUnmetItem is a type of the contract.
-type CheckAnswerLevelsItemUnmetItem struct {
-	Needs   []string `json:"needs,omitempty"`
-	Package string   `json:"package,omitempty"`
-}
-
-// CheckAnswerLevelsItem is a type of the contract.
-type CheckAnswerLevelsItem struct {
-	Digest *CheckAnswerLevelsItemDigest     `json:"digest,omitempty"`
-	Judged string                           `json:"judged,omitempty"`
-	Kept   []CheckAnswerLevelsItemKeptItem  `json:"kept,omitempty"`
-	Level  string                           `json:"level"`
-	Tests  []any                            `json:"tests,omitempty"`
-	Unmet  []CheckAnswerLevelsItemUnmetItem `json:"unmet,omitempty"`
-}
-
 // CheckAnswer is a type of the contract.
 type CheckAnswer struct {
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch  Fetch         `json:"fetch"`
-	Fetch  any                     `json:"fetch"`
+	Levels []LevelAnswer `json:"levels,omitempty"`
-	Levels []CheckAnswerLevelsItem `json:"levels,omitempty"`
 }
 
 // ComposeAnswer is a type of the contract.
@@ -289,6 +244,77 @@ type ComposeAnswer struct {
 	Verdict any `json:"verdict,omitempty"`
 }
 
+// FetchBesideItem is a type of the contract.
+type FetchBesideItem struct {
+	Commit     string `json:"commit"`
+	Repository string `json:"repository"`
+}
+
+// Fetch is what a build module's fetch tool is asked: the repository and the full commit, the pull request's ref when only its head carries the commit, the trunk commit to merge onto for a merge preview, the module's directory and named paths, the mesh packages to build against, and the sibling repositories placed beside.
+type Fetch struct {
+	// the trunk commit a merge preview merges onto
+	Base string `json:"base,omitempty"`
+	// the sibling repositories placed beside the fetched tree
+	Beside []FetchBesideItem `json:"beside,omitempty"`
+	// the full commit
+	Commit string `json:"commit"`
+	// the module's directory in the repository ("." for its root), with paths
+	Dir string `json:"dir,omitempty"`
+	// the version (a full commit) of each mesh package to build against, by its module path
+	Packages map[string]string `json:"packages,omitempty"`
+	// the paths the module names, relative to dir
+	Paths []string `json:"paths,omitempty"`
+	// the pull request's ref, when only its head carries the commit
+	Ref string `json:"ref,omitempty"`
+	// <owner>/<name>
+	Repository string `json:"repository"`
+}
+
+// LevelAnswerDigestNeedsItem is a type of the contract.
+type LevelAnswerDigestNeedsItem struct {
+	Needs   []string `json:"needs,omitempty"`
+	Package string   `json:"package,omitempty"`
+}
+
+// LevelAnswerDigestPackagesItem is a type of the contract.
+type LevelAnswerDigestPackagesItem struct {
+	Digest  string `json:"digest"`
+	Package string `json:"package"`
+}
+
+// LevelAnswerDigest is a type of the contract.
+type LevelAnswerDigest struct {
+	Beside       []string                        `json:"beside,omitempty"`
+	JudgedBy     string                          `json:"judged_by,omitempty"`
+	Level        string                          `json:"level,omitempty"`
+	Needs        []LevelAnswerDigestNeedsItem    `json:"needs,omitempty"`
+	Packages     []LevelAnswerDigestPackagesItem `json:"packages,omitempty"`
+	WithoutTests []string                        `json:"without_tests,omitempty"`
+}
+
+// LevelAnswerKeptItem is a type of the contract.
+type LevelAnswerKeptItem struct {
+	Digest  string `json:"digest,omitempty"`
+	Package string `json:"package,omitempty"`
+	Tests   int64  `json:"tests,omitempty"`
+}
+
+// LevelAnswerUnmetItem is a type of the contract.
+type LevelAnswerUnmetItem struct {
+	Needs   []string `json:"needs,omitempty"`
+	Package string   `json:"package,omitempty"`
+}
+
+// LevelAnswer is one level of a check ask: the digest's answer, the kept verdicts taken, one test result per test step run, and the packages the node could not test.
+type LevelAnswer struct {
+	Digest *LevelAnswerDigest     `json:"digest,omitempty"`
+	Judged string                 `json:"judged,omitempty"`
+	Kept   []LevelAnswerKeptItem  `json:"kept,omitempty"`
+	Level  string                 `json:"level"`
+	Tests  []any                  `json:"tests,omitempty"`
+	Unmet  []LevelAnswerUnmetItem `json:"unmet,omitempty"`
+}
+
 // Pause is whether the node takes no new ask.
 type Pause struct {
 	// when (RFC 3339 time)
@@ -308,10 +334,9 @@ type Step struct {
 	Owner string `json:"owner,omitempty"`
 	Phase string `json:"phase,omitempty"`
 	// when (RFC 3339 time)
-	PhaseAt string `json:"phase-at,omitempty"`
+	PhaseAt string      `json:"phase-at,omitempty"`
-	Reason  string `json:"reason,omitempty"`
+	Reason  string      `json:"reason,omitempty"`
-	// what the step answered
+	Result  *StepResult `json:"result,omitempty"`
-	Result any `json:"result,omitempty"`
 	// when (RFC 3339 time)
 	Started string `json:"started"`
 	// running, passed, failed or refused
@@ -322,37 +347,20 @@ type Step struct {
 	What string `json:"what,omitempty"`
 }
 
-// StepAskBuildArtifactsItem is a type of the contract.
-type StepAskBuildArtifactsItem struct {
-	Artifact string `json:"artifact"`
-	From     string `json:"from,omitempty"`
-	Seat     string `json:"seat,omitempty"`
-	Version  string `json:"version,omitempty"`
-}
-
-// StepAskBuildToolchain is a type of the contract.
-type StepAskBuildToolchain struct {
-	Language string `json:"language"`
-	Recipe   string `json:"recipe"`
-	Version  string `json:"version"`
-}
-
 // StepAskBuild is a type of the contract.
 type StepAskBuild struct {
-	Artifacts []StepAskBuildArtifactsItem `json:"artifacts"`
+	Artifacts []AskArtifact  `json:"artifacts"`
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch     *Fetch         `json:"fetch,omitempty"`
-	Fetch     any                    `json:"fetch,omitempty"`
+	Fp        string         `json:"fp,omitempty"`
-	Fp        string                 `json:"fp,omitempty"`
+	Module    string         `json:"module"`
-	Module    string                 `json:"module"`
+	Path      string         `json:"path,omitempty"`
-	Path      string                 `json:"path,omitempty"`
+	Publish   bool           `json:"publish,omitempty"`
-	Publish   bool                   `json:"publish,omitempty"`
+	Toolchain *ToolchainUsed `json:"toolchain,omitempty"`
-	Toolchain *StepAskBuildToolchain `json:"toolchain,omitempty"`
 }
 
 // StepAskCheck is a type of the contract.
 type StepAskCheck struct {
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch      Fetch    `json:"fetch"`
-	Fetch      any      `json:"fetch"`
 	Kept       bool     `json:"kept,omitempty"`
 	Levels     []string `json:"levels"`
 	Packages   []string `json:"packages,omitempty"`
@@ -363,9 +371,8 @@ type StepAskCheck struct {
 
 // StepAskCompose is a type of the contract.
 type StepAskCompose struct {
-	Dir string `json:"dir"`
+	Dir     string `json:"dir"`
-	// what the build module fetches: the repository, commit and directory, as the indexer states it
+	Fetch   Fetch  `json:"fetch"`
-	Fetch   any    `json:"fetch"`
 	Package string `json:"package"`
 	Reader  string `json:"reader,omitempty"`
 	// the compose-candidate request
@@ -392,6 +399,26 @@ type StepAsk struct {
 	V int64 `json:"v,omitempty"`
 }
 
+// StepResult is what a step answered, by the kind of ask: a build's artifacts, toolchain, imports and out-of-step modules; a check's fetch and levels; a compose's built, key and verdict; a declined ask's declined, needs and lacks. The fields of the kinds do not meet, so one layout holds the four.
+type StepResult struct {
+	Artifacts []BuiltArtifact `json:"artifacts,omitempty"`
+	Built     bool            `json:"built,omitempty"`
+	// the holder declined the ask: its node lacks what the ask needs
+	Declined bool     `json:"declined,omitempty"`
+	Fetch    *Fetch   `json:"fetch,omitempty"`
+	Imports  []string `json:"imports,omitempty"`
+	Key      string   `json:"key,omitempty"`
+	// what the holder's node lacks of it
+	Lacks  []string      `json:"lacks,omitempty"`
+	Levels []LevelAnswer `json:"levels,omitempty"`
+	// what the declined ask needs
+	Needs     []string       `json:"needs,omitempty"`
+	OutOfStep []string       `json:"out-of-step,omitempty"`
+	Toolchain *ToolchainUsed `json:"toolchain,omitempty"`
+	// the compose-candidate verdict (the composer's own layout)
+	Verdict any `json:"verdict,omitempty"`
+}
+
 // Toolchain is the toolchain a node reports.
 type Toolchain struct {
 	// when (RFC 3339 time)
@@ -404,6 +431,13 @@ type Toolchain struct {
 	Version string `json:"version"`
 }
 
+// ToolchainUsed is the toolchain a build was made with: the language, the installed version and the build module's recipe.
+type ToolchainUsed struct {
+	Language string `json:"language"`
+	Recipe   string `json:"recipe"`
+	Version  string `json:"version"`
+}
+
 // CurrentInput is what current takes.
 type CurrentInput struct {
 }

contracts/parts/build-step.json

@@ -64,7 +64,8 @@
         },
         "at": {
           "type": "string",
-          "description": "when (RFC 3339 time)"
+          "description": "when (RFC 3339 time)",
+          "format": "date-time"
         },
         "build": {
           "type": "object",
@@ -79,52 +80,19 @@
               "type": "string"
             },
             "fetch": {
-              "description": "what the build module fetches: the repository, commit and directory, as the indexer states it"
+              "$ref": "#/defs/Fetch"
             },
             "artifacts": {
               "type": "array",
               "items": {
-                "type": "object",
+                "$ref": "#/defs/AskArtifact"
-                "properties": {
-                  "artifact": {
-                    "type": "string"
-                  },
-                  "from": {
-                    "type": "string"
-                  },
-                  "seat": {
-                    "type": "string"
-                  },
-                  "version": {
-                    "type": "string"
-                  }
-                },
-                "required": [
-                  "artifact"
-                ]
               }
             },
             "publish": {
               "type": "boolean"
             },
             "toolchain": {
-              "type": "object",
+              "$ref": "#/defs/ToolchainUsed"
-              "properties": {
-                "language": {
-                  "type": "string"
-                },
-                "version": {
-                  "type": "string"
-                },
-                "recipe": {
-                  "type": "string"
-                }
-              },
-              "required": [
-                "language",
-                "version",
-                "recipe"
-              ]
             }
           },
           "required": [
@@ -136,7 +104,7 @@
           "type": "object",
           "properties": {
             "fetch": {
-              "description": "what the build module fetches: the repository, commit and directory, as the indexer states it"
+              "$ref": "#/defs/Fetch"
             },
             "levels": {
               "type": "array",
@@ -173,7 +141,7 @@
           "type": "object",
           "properties": {
             "fetch": {
-              "description": "what the build module fetches: the repository, commit and directory, as the indexer states it"
+              "$ref": "#/defs/Fetch"
             },
             "dir": {
               "type": "string"
@@ -223,42 +191,11 @@
         "artifacts": {
           "type": "array",
           "items": {
-            "type": "object",
+            "$ref": "#/defs/BuiltArtifact"
-            "properties": {
-              "artifact": {
-                "type": "string"
-              },
-              "digest": {
-                "type": "string"
-              },
-              "reference": {
-                "type": "string"
-              }
-            },
-            "required": [
-              "artifact",
-              "digest"
-            ]
           }
         },
         "toolchain": {
-          "type": "object",
+          "$ref": "#/defs/ToolchainUsed"
-          "properties": {
-            "language": {
-              "type": "string"
-            },
-            "version": {
-              "type": "string"
-            },
-            "recipe": {
-              "type": "string"
-            }
-          },
-          "required": [
-            "language",
-            "version",
-            "recipe"
-          ]
         },
         "imports": {
           "type": "array",
@@ -281,121 +218,12 @@
       "type": "object",
       "properties": {
         "fetch": {
-          "description": "what the build module fetches: the repository, commit and directory, as the indexer states it"
+          "$ref": "#/defs/Fetch"
         },
         "levels": {
           "type": "array",
           "items": {
-            "type": "object",
+            "$ref": "#/defs/LevelAnswer"
-            "properties": {
-              "level": {
-                "type": "string"
-              },
-              "judged": {
-                "type": "string"
-              },
-              "digest": {
-                "type": "object",
-                "properties": {
-                  "level": {
-                    "type": "string"
-                  },
-                  "packages": {
-                    "type": "array",
-                    "items": {
-                      "type": "object",
-                      "properties": {
-                        "package": {
-                          "type": "string"
-                        },
-                        "digest": {
-                          "type": "string"
-                        }
-                      },
-                      "required": [
-                        "package",
-                        "digest"
-                      ]
-                    }
-                  },
-                  "beside": {
-                    "type": "array",
-                    "items": {
-                      "type": "string"
-                    }
-                  },
-                  "without_tests": {
-                    "type": "array",
-                    "items": {
-                      "type": "string"
-                    }
-                  },
-                  "judged_by": {
-                    "type": "string"
-                  },
-                  "needs": {
-                    "type": "array",
-                    "items": {
-                      "type": "object",
-                      "properties": {
-                        "package": {
-                          "type": "string"
-                        },
-                        "needs": {
-                          "type": "array",
-                          "items": {
-                            "type": "string"
-                          }
-                        }
-                      }
-                    }
-                  }
-                }
-              },
-              "kept": {
-                "type": "array",
-                "items": {
-                  "type": "object",
-                  "properties": {
-                    "package": {
-                      "type": "string"
-                    },
-                    "digest": {
-                      "type": "string"
-                    },
-                    "tests": {
-                      "type": "integer"
-                    }
-                  }
-                }
-              },
-              "tests": {
-                "type": "array",
-                "items": {
-                  "description": "one test's result"
-                }
-              },
-              "unmet": {
-                "type": "array",
-                "items": {
-                  "type": "object",
-                  "properties": {
-                    "package": {
-                      "type": "string"
-                    },
-                    "needs": {
-                      "type": "array",
-                      "items": {
-                        "type": "string"
-                      }
-                    }
-                  }
-                }
-              }
-            },
-            "required": [
-              "level"
-            ]
           }
         }
       },
@@ -442,17 +270,19 @@
         },
         "started": {
           "type": "string",
-          "description": "when (RFC 3339 time)"
+          "description": "when (RFC 3339 time)",
+          "format": "date-time"
         },
         "ended": {
           "type": "string",
-          "description": "when (RFC 3339 time)"
+          "description": "when (RFC 3339 time)",
+          "format": "date-time"
         },
         "reason": {
           "type": "string"
         },
         "result": {
-          "description": "what the step answered"
+          "$ref": "#/defs/StepResult"
         },
         "what": {
           "type": "string"
@@ -462,7 +292,8 @@
         },
         "phase-at": {
           "type": "string",
-          "description": "when (RFC 3339 time)"
+          "description": "when (RFC 3339 time)",
+          "format": "date-time"
         },
         "owner": {
           "type": "string"
@@ -496,7 +327,8 @@
         },
         "at": {
           "type": "string",
-          "description": "when (RFC 3339 time)"
+          "description": "when (RFC 3339 time)",
+          "format": "date-time"
         }
       },
       "required": [
@@ -521,7 +353,8 @@
         },
         "at": {
           "type": "string",
-          "description": "when (RFC 3339 time)"
+          "description": "when (RFC 3339 time)",
+          "format": "date-time"
         }
       },
       "required": [
@@ -574,7 +407,8 @@
         },
         "at": {
           "type": "string",
-          "description": "when (RFC 3339 time)"
+          "description": "when (RFC 3339 time)",
+          "format": "date-time"
         }
       },
       "required": [
@@ -583,6 +417,305 @@
         "why"
       ],
       "description": "how many steps the node runs at once"
+    },
+    "Fetch": {
+      "type": "object",
+      "description": "what a build module's fetch tool is asked: the repository and the full commit, the pull request's ref when only its head carries the commit, the trunk commit to merge onto for a merge preview, the module's directory and named paths, the mesh packages to build against, and the sibling repositories placed beside",
+      "properties": {
+        "repository": {
+          "type": "string",
+          "description": "<owner>/<name>"
+        },
+        "commit": {
+          "type": "string",
+          "description": "the full commit"
+        },
+        "ref": {
+          "type": "string",
+          "description": "the pull request's ref, when only its head carries the commit"
+        },
+        "base": {
+          "type": "string",
+          "description": "the trunk commit a merge preview merges onto"
+        },
+        "dir": {
+          "type": "string",
+          "description": "the module's directory in the repository (\".\" for its root), with paths"
+        },
+        "paths": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          },
+          "description": "the paths the module names, relative to dir"
+        },
+        "packages": {
+          "type": "object",
+          "additionalProperties": {
+            "type": "string"
+          },
+          "description": "the version (a full commit) of each mesh package to build against, by its module path"
+        },
+        "beside": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "properties": {
+              "repository": {
+                "type": "string"
+              },
+              "commit": {
+                "type": "string"
+              }
+            },
+            "required": [
+              "repository",
+              "commit"
+            ]
+          },
+          "description": "the sibling repositories placed beside the fetched tree"
+        }
+      },
+      "required": [
+        "repository",
+        "commit"
+      ]
+    },
+    "ToolchainUsed": {
+      "type": "object",
+      "properties": {
+        "language": {
+          "type": "string"
+        },
+        "version": {
+          "type": "string"
+        },
+        "recipe": {
+          "type": "string"
+        }
+      },
+      "required": [
+        "language",
+        "version",
+        "recipe"
+      ],
+      "description": "the toolchain a build was made with: the language, the installed version and the build module's recipe"
+    },
+    "AskArtifact": {
+      "type": "object",
+      "properties": {
+        "artifact": {
+          "type": "string"
+        },
+        "from": {
+          "type": "string"
+        },
+        "seat": {
+          "type": "string"
+        },
+        "version": {
+          "type": "string"
+        }
+      },
+      "required": [
+        "artifact"
+      ],
+      "description": "one artifact of a build ask: built from the fetched tree, or copied from an upstream pin"
+    },
+    "BuiltArtifact": {
+      "type": "object",
+      "properties": {
+        "artifact": {
+          "type": "string"
+        },
+        "digest": {
+          "type": "string"
+        },
+        "reference": {
+          "type": "string"
+        }
+      },
+      "required": [
+        "artifact",
+        "digest"
+      ],
+      "description": "one artifact a build made: its digest and the reference it was published under"
+    },
+    "LevelAnswer": {
+      "type": "object",
+      "properties": {
+        "level": {
+          "type": "string"
+        },
+        "judged": {
+          "type": "string"
+        },
+        "digest": {
+          "type": "object",
+          "properties": {
+            "level": {
+              "type": "string"
+            },
+            "packages": {
+              "type": "array",
+              "items": {
+                "type": "object",
+                "properties": {
+                  "package": {
+                    "type": "string"
+                  },
+                  "digest": {
+                    "type": "string"
+                  }
+                },
+                "required": [
+                  "package",
+                  "digest"
+                ]
+              }
+            },
+            "beside": {
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            },
+            "without_tests": {
+              "type": "array",
+              "items": {
+                "type": "string"
+              }
+            },
+            "judged_by": {
+              "type": "string"
+            },
+            "needs": {
+              "type": "array",
+              "items": {
+                "type": "object",
+                "properties": {
+                  "package": {
+                    "type": "string"
+                  },
+                  "needs": {
+                    "type": "array",
+                    "items": {
+                      "type": "string"
+                    }
+                  }
+                }
+              }
+            }
+          }
+        },
+        "kept": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "properties": {
+              "package": {
+                "type": "string"
+              },
+              "digest": {
+                "type": "string"
+              },
+              "tests": {
+                "type": "integer"
+              }
+            }
+          }
+        },
+        "tests": {
+          "type": "array",
+          "items": {
+            "description": "one test's result"
+          }
+        },
+        "unmet": {
+          "type": "array",
+          "items": {
+            "type": "object",
+            "properties": {
+              "package": {
+                "type": "string"
+              },
+              "needs": {
+                "type": "array",
+                "items": {
+                  "type": "string"
+                }
+              }
+            }
+          }
+        }
+      },
+      "required": [
+        "level"
+      ],
+      "description": "one level of a check ask: the digest's answer, the kept verdicts taken, one test result per test step run, and the packages the node could not test"
+    },
+    "StepResult": {
+      "type": "object",
+      "description": "what a step answered, by the kind of ask: a build's artifacts, toolchain, imports and out-of-step modules; a check's fetch and levels; a compose's built, key and verdict; a declined ask's declined, needs and lacks. The fields of the kinds do not meet, so one layout holds the four",
+      "properties": {
+        "artifacts": {
+          "type": "array",
+          "items": {
+            "$ref": "#/defs/BuiltArtifact"
+          }
+        },
+        "toolchain": {
+          "$ref": "#/defs/ToolchainUsed"
+        },
+        "imports": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          }
+        },
+        "out-of-step": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          }
+        },
+        "fetch": {
+          "$ref": "#/defs/Fetch"
+        },
+        "levels": {
+          "type": "array",
+          "items": {
+            "$ref": "#/defs/LevelAnswer"
+          }
+        },
+        "built": {
+          "type": "boolean"
+        },
+        "key": {
+          "type": "string"
+        },
+        "verdict": {
+          "description": "the compose-candidate verdict (the composer's own layout)"
+        },
+        "declined": {
+          "type": "boolean",
+          "description": "the holder declined the ask: its node lacks what the ask needs"
+        },
+        "needs": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          },
+          "description": "what the declined ask needs"
+        },
+        "lacks": {
+          "type": "array",
+          "items": {
+            "type": "string"
+          },
+          "description": "what the holder's node lacks of it"
+        }
+      }
     }
   }
 }

contracts/seats/node-build-go/fixtures/states.json

@@ -59,5 +59,145 @@
         ]
       }
     }
+  },
+  {
+    "name": "a check ask with its fetch, siblings and levels",
+    "of": "accept:check",
+    "subject": "mesh.seat.node-build-go.accept.check",
+    "given": {
+      "v": 1,
+      "id": "c3d4",
+      "kind": "check",
+      "language": "go",
+      "asker": "mesh-delivery-checker",
+      "at": "2026-11-05T10:00:00Z",
+      "check": {
+        "fetch": {
+          "repository": "novox/mesh-catalog",
+          "commit": "0123456789abcdef0123456789abcdef01234567",
+          "ref": "refs/pull/7/head",
+          "base": "89abcdef0123456789abcdef0123456789abcdef",
+          "beside": [
+            {
+              "repository": "novox/mesh-sdk",
+              "commit": "fedcba9876543210fedcba9876543210fedcba98"
+            }
+          ],
+          "packages": {
+            "git.novox.be/novox/mesh-sdk/go": "fedcba9876543210fedcba9876543210fedcba98"
+          }
+        },
+        "levels": [
+          "unit",
+          "integration"
+        ],
+        "kept": true
+      }
+    }
+  },
+  {
+    "name": "a finished build step with its artifacts",
+    "of": "state:steps/<node>.<id>",
+    "given": {
+      "v": 1,
+      "id": "a1b2",
+      "tool": "build",
+      "node": "ace",
+      "state": "passed",
+      "started": "2026-11-05T10:00:00Z",
+      "ended": "2026-11-05T10:03:00Z",
+      "result": {
+        "artifacts": [
+          {
+            "artifact": "go",
+            "digest": "sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+            "reference": "container-image-registry/nats/go@sha256:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
+          }
+        ],
+        "toolchain": {
+          "language": "go",
+          "version": "1.26.0",
+          "recipe": "1"
+        },
+        "imports": [
+          "git.novox.be/novox/mesh-sdk/go"
+        ]
+      }
+    }
+  },
+  {
+    "name": "a finished check step with its levels",
+    "of": "state:steps/<node>.<id>",
+    "given": {
+      "v": 1,
+      "id": "c3d4",
+      "tool": "check",
+      "node": "ace",
+      "state": "passed",
+      "started": "2026-11-05T10:00:00Z",
+      "ended": "2026-11-05T10:06:00Z",
+      "result": {
+        "fetch": {
+          "repository": "novox/mesh-catalog",
+          "commit": "0123456789abcdef0123456789abcdef01234567"
+        },
+        "levels": [
+          {
+            "level": "unit",
+            "digest": {
+              "level": "unit",
+              "packages": [
+                {
+                  "package": "./modules/a",
+                  "digest": "sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
+                }
+              ]
+            },
+            "kept": [
+              {
+                "package": "./modules/a",
+                "digest": "sha256:bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb",
+                "tests": 12
+              }
+            ],
+            "tests": [
+              {
+                "package": "./modules/b",
+                "pass": true
+              }
+            ],
+            "unmet": [
+              {
+                "package": "./modules/c",
+                "needs": [
+                  "docker"
+                ]
+              }
+            ]
+          }
+        ]
+      }
+    }
+  },
+  {
+    "name": "a declined step",
+    "of": "state:steps/<node>.<id>",
+    "given": {
+      "v": 1,
+      "id": "c3d5",
+      "tool": "check",
+      "node": "ace",
+      "state": "refused",
+      "started": "2026-11-05T10:00:00Z",
+      "result": {
+        "declined": true,
+        "needs": [
+          "docker"
+        ],
+        "lacks": [
+          "docker"
+        ]
+      }
+    }
   }
 ]

contracts/ts/seats/nodebuildgo/src/index.ts

@@ -102,20 +102,22 @@ export function parseToolchainsByNodeLanguageKey(key: string): { node: string; l
   return { node, language };
 }
 
+export type AskArtifact = buildStep.AskArtifact;
 export type BuildAnswer = buildStep.BuildAnswer;
-export type BuildAnswerArtifactsItem = buildStep.BuildAnswerArtifactsItem;
+export type BuiltArtifact = buildStep.BuiltArtifact;
-export type BuildAnswerToolchain = buildStep.BuildAnswerToolchain;
 export type Capacity = buildStep.Capacity;
 export type CheckAnswer = buildStep.CheckAnswer;
-export type CheckAnswerLevelsItem = buildStep.CheckAnswerLevelsItem;
-export type CheckAnswerLevelsItemDigest = buildStep.CheckAnswerLevelsItemDigest;
-export type CheckAnswerLevelsItemDigestNeedsItem = buildStep.CheckAnswerLevelsItemDigestNeedsItem;
-export type CheckAnswerLevelsItemDigestPackagesItem = buildStep.CheckAnswerLevelsItemDigestPackagesItem;
-export type CheckAnswerLevelsItemKeptItem = buildStep.CheckAnswerLevelsItemKeptItem;
-export type CheckAnswerLevelsItemUnmetItem = buildStep.CheckAnswerLevelsItemUnmetItem;
 export type ComposeAnswer = buildStep.ComposeAnswer;
 export type CurrentAnswer = buildStep.CurrentAnswer;
 export type CurrentInput = buildStep.CurrentInput;
+export type Fetch = buildStep.Fetch;
+export type FetchBesideItem = buildStep.FetchBesideItem;
+export type LevelAnswer = buildStep.LevelAnswer;
+export type LevelAnswerDigest = buildStep.LevelAnswerDigest;
+export type LevelAnswerDigestNeedsItem = buildStep.LevelAnswerDigestNeedsItem;
+export type LevelAnswerDigestPackagesItem = buildStep.LevelAnswerDigestPackagesItem;
+export type LevelAnswerKeptItem = buildStep.LevelAnswerKeptItem;
+export type LevelAnswerUnmetItem = buildStep.LevelAnswerUnmetItem;
 export type Pause = buildStep.Pause;
 export type PauseAnswer = buildStep.PauseAnswer;
 export type PauseInput = buildStep.PauseInput;
@@ -124,11 +126,11 @@ export type ResumeInput = buildStep.ResumeInput;
 export type Step = buildStep.Step;
 export type StepAsk = buildStep.StepAsk;
 export type StepAskBuild = buildStep.StepAskBuild;
-export type StepAskBuildArtifactsItem = buildStep.StepAskBuildArtifactsItem;
-export type StepAskBuildToolchain = buildStep.StepAskBuildToolchain;
 export type StepAskCheck = buildStep.StepAskCheck;
 export type StepAskCompose = buildStep.StepAskCompose;
+export type StepResult = buildStep.StepResult;
 export type Toolchain = buildStep.Toolchain;
+export type ToolchainUsed = buildStep.ToolchainUsed;
 
 /** is the body of delivery. */
 export type DeliveryAccept = StepAsk;

contracts/ts/seats/nodebuildgo/src/parts/build-step.ts

@@ -8,23 +8,26 @@ export const verbs = {
   resume: "resume",
 } as const;
 
-export interface BuildAnswerArtifactsItem {
+/** one artifact of a build ask: built from the fetched tree, or copied from an upstream pin */
+export interface AskArtifact {
   "artifact": string;
-  "digest": string;
+  "from"?: string;
-  "reference"?: string;
+  "seat"?: string;
-}
+  "version"?: string;
-
-export interface BuildAnswerToolchain {
-  "language": string;
-  "recipe": string;
-  "version": string;
 }
 
 export interface BuildAnswer {
-  "artifacts": BuildAnswerArtifactsItem[];
+  "artifacts": BuiltArtifact[];
   "imports"?: string[];
   "out-of-step"?: string[];
-  "toolchain"?: BuildAnswerToolchain;
+  "toolchain"?: ToolchainUsed;
+}
+
+/** one artifact a build made: its digest and the reference it was published under */
+export interface BuiltArtifact {
+  "artifact": string;
+  "digest": string;
+  "reference"?: string;
 }
 
 /** how many steps the node runs at once */
@@ -47,49 +50,9 @@ export interface Capacity {
   "why": string;
 }
 
-export interface CheckAnswerLevelsItemDigestNeedsItem {
-  "needs"?: string[];
-  "package"?: string;
-}
-
-export interface CheckAnswerLevelsItemDigestPackagesItem {
-  "digest": string;
-  "package": string;
-}
-
-export interface CheckAnswerLevelsItemDigest {
-  "beside"?: string[];
-  "judged_by"?: string;
-  "level"?: string;
-  "needs"?: CheckAnswerLevelsItemDigestNeedsItem[];
-  "packages"?: CheckAnswerLevelsItemDigestPackagesItem[];
-  "without_tests"?: string[];
-}
-
-export interface CheckAnswerLevelsItemKeptItem {
-  "digest"?: string;
-  "package"?: string;
-  "tests"?: number;
-}
-
-export interface CheckAnswerLevelsItemUnmetItem {
-  "needs"?: string[];
-  "package"?: string;
-}
-
-export interface CheckAnswerLevelsItem {
-  "digest"?: CheckAnswerLevelsItemDigest;
-  "judged"?: string;
-  "kept"?: CheckAnswerLevelsItemKeptItem[];
-  "level": string;
-  "tests"?: unknown[];
-  "unmet"?: CheckAnswerLevelsItemUnmetItem[];
-}
-
 export interface CheckAnswer {
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
+  "levels"?: LevelAnswer[];
-  "levels"?: CheckAnswerLevelsItem[];
 }
 
 export interface ComposeAnswer {
@@ -99,6 +62,71 @@ export interface ComposeAnswer {
   "verdict"?: unknown;
 }
 
+export interface FetchBesideItem {
+  "commit": string;
+  "repository": string;
+}
+
+/** what a build module's fetch tool is asked: the repository and the full commit, the pull request's ref when only its head carries the commit, the trunk commit to merge onto for a merge preview, the module's directory and named paths, the mesh packages to build against, and the sibling repositories placed beside */
+export interface Fetch {
+  /** the trunk commit a merge preview merges onto */
+  "base"?: string;
+  /** the sibling repositories placed beside the fetched tree */
+  "beside"?: FetchBesideItem[];
+  /** the full commit */
+  "commit": string;
+  /** the module's directory in the repository ("." for its root), with paths */
+  "dir"?: string;
+  /** the version (a full commit) of each mesh package to build against, by its module path */
+  "packages"?: Record<string, string>;
+  /** the paths the module names, relative to dir */
+  "paths"?: string[];
+  /** the pull request's ref, when only its head carries the commit */
+  "ref"?: string;
+  /** <owner>/<name> */
+  "repository": string;
+}
+
+export interface LevelAnswerDigestNeedsItem {
+  "needs"?: string[];
+  "package"?: string;
+}
+
+export interface LevelAnswerDigestPackagesItem {
+  "digest": string;
+  "package": string;
+}
+
+export interface LevelAnswerDigest {
+  "beside"?: string[];
+  "judged_by"?: string;
+  "level"?: string;
+  "needs"?: LevelAnswerDigestNeedsItem[];
+  "packages"?: LevelAnswerDigestPackagesItem[];
+  "without_tests"?: string[];
+}
+
+export interface LevelAnswerKeptItem {
+  "digest"?: string;
+  "package"?: string;
+  "tests"?: number;
+}
+
+export interface LevelAnswerUnmetItem {
+  "needs"?: string[];
+  "package"?: string;
+}
+
+/** one level of a check ask: the digest's answer, the kept verdicts taken, one test result per test step run, and the packages the node could not test */
+export interface LevelAnswer {
+  "digest"?: LevelAnswerDigest;
+  "judged"?: string;
+  "kept"?: LevelAnswerKeptItem[];
+  "level": string;
+  "tests"?: unknown[];
+  "unmet"?: LevelAnswerUnmetItem[];
+}
+
 /** whether the node takes no new ask */
 export interface Pause {
   /** when (RFC 3339 time) */
@@ -120,8 +148,7 @@ export interface Step {
   /** when (RFC 3339 time) */
   "phase-at"?: string;
   "reason"?: string;
-  /** what the step answered */
+  "result"?: StepResult;
-  "result"?: unknown;
   /** when (RFC 3339 time) */
   "started": string;
   /** running, passed, failed or refused */
@@ -132,33 +159,18 @@ export interface Step {
   "what"?: string;
 }
 
-export interface StepAskBuildArtifactsItem {
-  "artifact": string;
-  "from"?: string;
-  "seat"?: string;
-  "version"?: string;
-}
-
-export interface StepAskBuildToolchain {
-  "language": string;
-  "recipe": string;
-  "version": string;
-}
-
 export interface StepAskBuild {
-  "artifacts": StepAskBuildArtifactsItem[];
+  "artifacts": AskArtifact[];
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch"?: Fetch;
-  "fetch"?: unknown;
   "fp"?: string;
   "module": string;
   "path"?: string;
   "publish"?: boolean;
-  "toolchain"?: StepAskBuildToolchain;
+  "toolchain"?: ToolchainUsed;
 }
 
 export interface StepAskCheck {
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
   "kept"?: boolean;
   "levels": string[];
   "packages"?: string[];
@@ -169,8 +181,7 @@ export interface StepAskCheck {
 
 export interface StepAskCompose {
   "dir": string;
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
   "package": string;
   "reader"?: string;
   /** the compose-candidate request */
@@ -197,6 +208,26 @@ export interface StepAsk {
   "v"?: number;
 }
 
+/** what a step answered, by the kind of ask: a build's artifacts, toolchain, imports and out-of-step modules; a check's fetch and levels; a compose's built, key and verdict; a declined ask's declined, needs and lacks. The fields of the kinds do not meet, so one layout holds the four */
+export interface StepResult {
+  "artifacts"?: BuiltArtifact[];
+  "built"?: boolean;
+  /** the holder declined the ask: its node lacks what the ask needs */
+  "declined"?: boolean;
+  "fetch"?: Fetch;
+  "imports"?: string[];
+  "key"?: string;
+  /** what the holder's node lacks of it */
+  "lacks"?: string[];
+  "levels"?: LevelAnswer[];
+  /** what the declined ask needs */
+  "needs"?: string[];
+  "out-of-step"?: string[];
+  "toolchain"?: ToolchainUsed;
+  /** the compose-candidate verdict (the composer's own layout) */
+  "verdict"?: unknown;
+}
+
 /** the toolchain a node reports */
 export interface Toolchain {
   /** when (RFC 3339 time) */
@@ -209,6 +240,13 @@ export interface Toolchain {
   "version": string;
 }
 
+/** the toolchain a build was made with: the language, the installed version and the build module's recipe */
+export interface ToolchainUsed {
+  "language": string;
+  "recipe": string;
+  "version": string;
+}
+
 /** is what current takes. */
 export interface CurrentInput {
 }

contracts/ts/seats/nodebuildimage/src/index.ts

@@ -102,20 +102,22 @@ export function parseToolchainsByNodeLanguageKey(key: string): { node: string; l
   return { node, language };
 }
 
+export type AskArtifact = buildStep.AskArtifact;
 export type BuildAnswer = buildStep.BuildAnswer;
-export type BuildAnswerArtifactsItem = buildStep.BuildAnswerArtifactsItem;
+export type BuiltArtifact = buildStep.BuiltArtifact;
-export type BuildAnswerToolchain = buildStep.BuildAnswerToolchain;
 export type Capacity = buildStep.Capacity;
 export type CheckAnswer = buildStep.CheckAnswer;
-export type CheckAnswerLevelsItem = buildStep.CheckAnswerLevelsItem;
-export type CheckAnswerLevelsItemDigest = buildStep.CheckAnswerLevelsItemDigest;
-export type CheckAnswerLevelsItemDigestNeedsItem = buildStep.CheckAnswerLevelsItemDigestNeedsItem;
-export type CheckAnswerLevelsItemDigestPackagesItem = buildStep.CheckAnswerLevelsItemDigestPackagesItem;
-export type CheckAnswerLevelsItemKeptItem = buildStep.CheckAnswerLevelsItemKeptItem;
-export type CheckAnswerLevelsItemUnmetItem = buildStep.CheckAnswerLevelsItemUnmetItem;
 export type ComposeAnswer = buildStep.ComposeAnswer;
 export type CurrentAnswer = buildStep.CurrentAnswer;
 export type CurrentInput = buildStep.CurrentInput;
+export type Fetch = buildStep.Fetch;
+export type FetchBesideItem = buildStep.FetchBesideItem;
+export type LevelAnswer = buildStep.LevelAnswer;
+export type LevelAnswerDigest = buildStep.LevelAnswerDigest;
+export type LevelAnswerDigestNeedsItem = buildStep.LevelAnswerDigestNeedsItem;
+export type LevelAnswerDigestPackagesItem = buildStep.LevelAnswerDigestPackagesItem;
+export type LevelAnswerKeptItem = buildStep.LevelAnswerKeptItem;
+export type LevelAnswerUnmetItem = buildStep.LevelAnswerUnmetItem;
 export type Pause = buildStep.Pause;
 export type PauseAnswer = buildStep.PauseAnswer;
 export type PauseInput = buildStep.PauseInput;
@@ -124,11 +126,11 @@ export type ResumeInput = buildStep.ResumeInput;
 export type Step = buildStep.Step;
 export type StepAsk = buildStep.StepAsk;
 export type StepAskBuild = buildStep.StepAskBuild;
-export type StepAskBuildArtifactsItem = buildStep.StepAskBuildArtifactsItem;
-export type StepAskBuildToolchain = buildStep.StepAskBuildToolchain;
 export type StepAskCheck = buildStep.StepAskCheck;
 export type StepAskCompose = buildStep.StepAskCompose;
+export type StepResult = buildStep.StepResult;
 export type Toolchain = buildStep.Toolchain;
+export type ToolchainUsed = buildStep.ToolchainUsed;
 
 /** is the body of delivery. */
 export type DeliveryAccept = StepAsk;

contracts/ts/seats/nodebuildimage/src/parts/build-step.ts

@@ -8,23 +8,26 @@ export const verbs = {
   resume: "resume",
 } as const;
 
-export interface BuildAnswerArtifactsItem {
+/** one artifact of a build ask: built from the fetched tree, or copied from an upstream pin */
+export interface AskArtifact {
   "artifact": string;
-  "digest": string;
+  "from"?: string;
-  "reference"?: string;
+  "seat"?: string;
-}
+  "version"?: string;
-
-export interface BuildAnswerToolchain {
-  "language": string;
-  "recipe": string;
-  "version": string;
 }
 
 export interface BuildAnswer {
-  "artifacts": BuildAnswerArtifactsItem[];
+  "artifacts": BuiltArtifact[];
   "imports"?: string[];
   "out-of-step"?: string[];
-  "toolchain"?: BuildAnswerToolchain;
+  "toolchain"?: ToolchainUsed;
+}
+
+/** one artifact a build made: its digest and the reference it was published under */
+export interface BuiltArtifact {
+  "artifact": string;
+  "digest": string;
+  "reference"?: string;
 }
 
 /** how many steps the node runs at once */
@@ -47,49 +50,9 @@ export interface Capacity {
   "why": string;
 }
 
-export interface CheckAnswerLevelsItemDigestNeedsItem {
-  "needs"?: string[];
-  "package"?: string;
-}
-
-export interface CheckAnswerLevelsItemDigestPackagesItem {
-  "digest": string;
-  "package": string;
-}
-
-export interface CheckAnswerLevelsItemDigest {
-  "beside"?: string[];
-  "judged_by"?: string;
-  "level"?: string;
-  "needs"?: CheckAnswerLevelsItemDigestNeedsItem[];
-  "packages"?: CheckAnswerLevelsItemDigestPackagesItem[];
-  "without_tests"?: string[];
-}
-
-export interface CheckAnswerLevelsItemKeptItem {
-  "digest"?: string;
-  "package"?: string;
-  "tests"?: number;
-}
-
-export interface CheckAnswerLevelsItemUnmetItem {
-  "needs"?: string[];
-  "package"?: string;
-}
-
-export interface CheckAnswerLevelsItem {
-  "digest"?: CheckAnswerLevelsItemDigest;
-  "judged"?: string;
-  "kept"?: CheckAnswerLevelsItemKeptItem[];
-  "level": string;
-  "tests"?: unknown[];
-  "unmet"?: CheckAnswerLevelsItemUnmetItem[];
-}
-
 export interface CheckAnswer {
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
+  "levels"?: LevelAnswer[];
-  "levels"?: CheckAnswerLevelsItem[];
 }
 
 export interface ComposeAnswer {
@@ -99,6 +62,71 @@ export interface ComposeAnswer {
   "verdict"?: unknown;
 }
 
+export interface FetchBesideItem {
+  "commit": string;
+  "repository": string;
+}
+
+/** what a build module's fetch tool is asked: the repository and the full commit, the pull request's ref when only its head carries the commit, the trunk commit to merge onto for a merge preview, the module's directory and named paths, the mesh packages to build against, and the sibling repositories placed beside */
+export interface Fetch {
+  /** the trunk commit a merge preview merges onto */
+  "base"?: string;
+  /** the sibling repositories placed beside the fetched tree */
+  "beside"?: FetchBesideItem[];
+  /** the full commit */
+  "commit": string;
+  /** the module's directory in the repository ("." for its root), with paths */
+  "dir"?: string;
+  /** the version (a full commit) of each mesh package to build against, by its module path */
+  "packages"?: Record<string, string>;
+  /** the paths the module names, relative to dir */
+  "paths"?: string[];
+  /** the pull request's ref, when only its head carries the commit */
+  "ref"?: string;
+  /** <owner>/<name> */
+  "repository": string;
+}
+
+export interface LevelAnswerDigestNeedsItem {
+  "needs"?: string[];
+  "package"?: string;
+}
+
+export interface LevelAnswerDigestPackagesItem {
+  "digest": string;
+  "package": string;
+}
+
+export interface LevelAnswerDigest {
+  "beside"?: string[];
+  "judged_by"?: string;
+  "level"?: string;
+  "needs"?: LevelAnswerDigestNeedsItem[];
+  "packages"?: LevelAnswerDigestPackagesItem[];
+  "without_tests"?: string[];
+}
+
+export interface LevelAnswerKeptItem {
+  "digest"?: string;
+  "package"?: string;
+  "tests"?: number;
+}
+
+export interface LevelAnswerUnmetItem {
+  "needs"?: string[];
+  "package"?: string;
+}
+
+/** one level of a check ask: the digest's answer, the kept verdicts taken, one test result per test step run, and the packages the node could not test */
+export interface LevelAnswer {
+  "digest"?: LevelAnswerDigest;
+  "judged"?: string;
+  "kept"?: LevelAnswerKeptItem[];
+  "level": string;
+  "tests"?: unknown[];
+  "unmet"?: LevelAnswerUnmetItem[];
+}
+
 /** whether the node takes no new ask */
 export interface Pause {
   /** when (RFC 3339 time) */
@@ -120,8 +148,7 @@ export interface Step {
   /** when (RFC 3339 time) */
   "phase-at"?: string;
   "reason"?: string;
-  /** what the step answered */
+  "result"?: StepResult;
-  "result"?: unknown;
   /** when (RFC 3339 time) */
   "started": string;
   /** running, passed, failed or refused */
@@ -132,33 +159,18 @@ export interface Step {
   "what"?: string;
 }
 
-export interface StepAskBuildArtifactsItem {
-  "artifact": string;
-  "from"?: string;
-  "seat"?: string;
-  "version"?: string;
-}
-
-export interface StepAskBuildToolchain {
-  "language": string;
-  "recipe": string;
-  "version": string;
-}
-
 export interface StepAskBuild {
-  "artifacts": StepAskBuildArtifactsItem[];
+  "artifacts": AskArtifact[];
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch"?: Fetch;
-  "fetch"?: unknown;
   "fp"?: string;
   "module": string;
   "path"?: string;
   "publish"?: boolean;
-  "toolchain"?: StepAskBuildToolchain;
+  "toolchain"?: ToolchainUsed;
 }
 
 export interface StepAskCheck {
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
   "kept"?: boolean;
   "levels": string[];
   "packages"?: string[];
@@ -169,8 +181,7 @@ export interface StepAskCheck {
 
 export interface StepAskCompose {
   "dir": string;
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
   "package": string;
   "reader"?: string;
   /** the compose-candidate request */
@@ -197,6 +208,26 @@ export interface StepAsk {
   "v"?: number;
 }
 
+/** what a step answered, by the kind of ask: a build's artifacts, toolchain, imports and out-of-step modules; a check's fetch and levels; a compose's built, key and verdict; a declined ask's declined, needs and lacks. The fields of the kinds do not meet, so one layout holds the four */
+export interface StepResult {
+  "artifacts"?: BuiltArtifact[];
+  "built"?: boolean;
+  /** the holder declined the ask: its node lacks what the ask needs */
+  "declined"?: boolean;
+  "fetch"?: Fetch;
+  "imports"?: string[];
+  "key"?: string;
+  /** what the holder's node lacks of it */
+  "lacks"?: string[];
+  "levels"?: LevelAnswer[];
+  /** what the declined ask needs */
+  "needs"?: string[];
+  "out-of-step"?: string[];
+  "toolchain"?: ToolchainUsed;
+  /** the compose-candidate verdict (the composer's own layout) */
+  "verdict"?: unknown;
+}
+
 /** the toolchain a node reports */
 export interface Toolchain {
   /** when (RFC 3339 time) */
@@ -209,6 +240,13 @@ export interface Toolchain {
   "version": string;
 }
 
+/** the toolchain a build was made with: the language, the installed version and the build module's recipe */
+export interface ToolchainUsed {
+  "language": string;
+  "recipe": string;
+  "version": string;
+}
+
 /** is what current takes. */
 export interface CurrentInput {
 }

contracts/ts/seats/nodebuildnode/src/index.ts

@@ -102,20 +102,22 @@ export function parseToolchainsByNodeLanguageKey(key: string): { node: string; l
   return { node, language };
 }
 
+export type AskArtifact = buildStep.AskArtifact;
 export type BuildAnswer = buildStep.BuildAnswer;
-export type BuildAnswerArtifactsItem = buildStep.BuildAnswerArtifactsItem;
+export type BuiltArtifact = buildStep.BuiltArtifact;
-export type BuildAnswerToolchain = buildStep.BuildAnswerToolchain;
 export type Capacity = buildStep.Capacity;
 export type CheckAnswer = buildStep.CheckAnswer;
-export type CheckAnswerLevelsItem = buildStep.CheckAnswerLevelsItem;
-export type CheckAnswerLevelsItemDigest = buildStep.CheckAnswerLevelsItemDigest;
-export type CheckAnswerLevelsItemDigestNeedsItem = buildStep.CheckAnswerLevelsItemDigestNeedsItem;
-export type CheckAnswerLevelsItemDigestPackagesItem = buildStep.CheckAnswerLevelsItemDigestPackagesItem;
-export type CheckAnswerLevelsItemKeptItem = buildStep.CheckAnswerLevelsItemKeptItem;
-export type CheckAnswerLevelsItemUnmetItem = buildStep.CheckAnswerLevelsItemUnmetItem;
 export type ComposeAnswer = buildStep.ComposeAnswer;
 export type CurrentAnswer = buildStep.CurrentAnswer;
 export type CurrentInput = buildStep.CurrentInput;
+export type Fetch = buildStep.Fetch;
+export type FetchBesideItem = buildStep.FetchBesideItem;
+export type LevelAnswer = buildStep.LevelAnswer;
+export type LevelAnswerDigest = buildStep.LevelAnswerDigest;
+export type LevelAnswerDigestNeedsItem = buildStep.LevelAnswerDigestNeedsItem;
+export type LevelAnswerDigestPackagesItem = buildStep.LevelAnswerDigestPackagesItem;
+export type LevelAnswerKeptItem = buildStep.LevelAnswerKeptItem;
+export type LevelAnswerUnmetItem = buildStep.LevelAnswerUnmetItem;
 export type Pause = buildStep.Pause;
 export type PauseAnswer = buildStep.PauseAnswer;
 export type PauseInput = buildStep.PauseInput;
@@ -124,11 +126,11 @@ export type ResumeInput = buildStep.ResumeInput;
 export type Step = buildStep.Step;
 export type StepAsk = buildStep.StepAsk;
 export type StepAskBuild = buildStep.StepAskBuild;
-export type StepAskBuildArtifactsItem = buildStep.StepAskBuildArtifactsItem;
-export type StepAskBuildToolchain = buildStep.StepAskBuildToolchain;
 export type StepAskCheck = buildStep.StepAskCheck;
 export type StepAskCompose = buildStep.StepAskCompose;
+export type StepResult = buildStep.StepResult;
 export type Toolchain = buildStep.Toolchain;
+export type ToolchainUsed = buildStep.ToolchainUsed;
 
 /** is the body of delivery. */
 export type DeliveryAccept = StepAsk;

contracts/ts/seats/nodebuildnode/src/parts/build-step.ts

@@ -8,23 +8,26 @@ export const verbs = {
   resume: "resume",
 } as const;
 
-export interface BuildAnswerArtifactsItem {
+/** one artifact of a build ask: built from the fetched tree, or copied from an upstream pin */
+export interface AskArtifact {
   "artifact": string;
-  "digest": string;
+  "from"?: string;
-  "reference"?: string;
+  "seat"?: string;
-}
+  "version"?: string;
-
-export interface BuildAnswerToolchain {
-  "language": string;
-  "recipe": string;
-  "version": string;
 }
 
 export interface BuildAnswer {
-  "artifacts": BuildAnswerArtifactsItem[];
+  "artifacts": BuiltArtifact[];
   "imports"?: string[];
   "out-of-step"?: string[];
-  "toolchain"?: BuildAnswerToolchain;
+  "toolchain"?: ToolchainUsed;
+}
+
+/** one artifact a build made: its digest and the reference it was published under */
+export interface BuiltArtifact {
+  "artifact": string;
+  "digest": string;
+  "reference"?: string;
 }
 
 /** how many steps the node runs at once */
@@ -47,49 +50,9 @@ export interface Capacity {
   "why": string;
 }
 
-export interface CheckAnswerLevelsItemDigestNeedsItem {
-  "needs"?: string[];
-  "package"?: string;
-}
-
-export interface CheckAnswerLevelsItemDigestPackagesItem {
-  "digest": string;
-  "package": string;
-}
-
-export interface CheckAnswerLevelsItemDigest {
-  "beside"?: string[];
-  "judged_by"?: string;
-  "level"?: string;
-  "needs"?: CheckAnswerLevelsItemDigestNeedsItem[];
-  "packages"?: CheckAnswerLevelsItemDigestPackagesItem[];
-  "without_tests"?: string[];
-}
-
-export interface CheckAnswerLevelsItemKeptItem {
-  "digest"?: string;
-  "package"?: string;
-  "tests"?: number;
-}
-
-export interface CheckAnswerLevelsItemUnmetItem {
-  "needs"?: string[];
-  "package"?: string;
-}
-
-export interface CheckAnswerLevelsItem {
-  "digest"?: CheckAnswerLevelsItemDigest;
-  "judged"?: string;
-  "kept"?: CheckAnswerLevelsItemKeptItem[];
-  "level": string;
-  "tests"?: unknown[];
-  "unmet"?: CheckAnswerLevelsItemUnmetItem[];
-}
-
 export interface CheckAnswer {
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
+  "levels"?: LevelAnswer[];
-  "levels"?: CheckAnswerLevelsItem[];
 }
 
 export interface ComposeAnswer {
@@ -99,6 +62,71 @@ export interface ComposeAnswer {
   "verdict"?: unknown;
 }
 
+export interface FetchBesideItem {
+  "commit": string;
+  "repository": string;
+}
+
+/** what a build module's fetch tool is asked: the repository and the full commit, the pull request's ref when only its head carries the commit, the trunk commit to merge onto for a merge preview, the module's directory and named paths, the mesh packages to build against, and the sibling repositories placed beside */
+export interface Fetch {
+  /** the trunk commit a merge preview merges onto */
+  "base"?: string;
+  /** the sibling repositories placed beside the fetched tree */
+  "beside"?: FetchBesideItem[];
+  /** the full commit */
+  "commit": string;
+  /** the module's directory in the repository ("." for its root), with paths */
+  "dir"?: string;
+  /** the version (a full commit) of each mesh package to build against, by its module path */
+  "packages"?: Record<string, string>;
+  /** the paths the module names, relative to dir */
+  "paths"?: string[];
+  /** the pull request's ref, when only its head carries the commit */
+  "ref"?: string;
+  /** <owner>/<name> */
+  "repository": string;
+}
+
+export interface LevelAnswerDigestNeedsItem {
+  "needs"?: string[];
+  "package"?: string;
+}
+
+export interface LevelAnswerDigestPackagesItem {
+  "digest": string;
+  "package": string;
+}
+
+export interface LevelAnswerDigest {
+  "beside"?: string[];
+  "judged_by"?: string;
+  "level"?: string;
+  "needs"?: LevelAnswerDigestNeedsItem[];
+  "packages"?: LevelAnswerDigestPackagesItem[];
+  "without_tests"?: string[];
+}
+
+export interface LevelAnswerKeptItem {
+  "digest"?: string;
+  "package"?: string;
+  "tests"?: number;
+}
+
+export interface LevelAnswerUnmetItem {
+  "needs"?: string[];
+  "package"?: string;
+}
+
+/** one level of a check ask: the digest's answer, the kept verdicts taken, one test result per test step run, and the packages the node could not test */
+export interface LevelAnswer {
+  "digest"?: LevelAnswerDigest;
+  "judged"?: string;
+  "kept"?: LevelAnswerKeptItem[];
+  "level": string;
+  "tests"?: unknown[];
+  "unmet"?: LevelAnswerUnmetItem[];
+}
+
 /** whether the node takes no new ask */
 export interface Pause {
   /** when (RFC 3339 time) */
@@ -120,8 +148,7 @@ export interface Step {
   /** when (RFC 3339 time) */
   "phase-at"?: string;
   "reason"?: string;
-  /** what the step answered */
+  "result"?: StepResult;
-  "result"?: unknown;
   /** when (RFC 3339 time) */
   "started": string;
   /** running, passed, failed or refused */
@@ -132,33 +159,18 @@ export interface Step {
   "what"?: string;
 }
 
-export interface StepAskBuildArtifactsItem {
-  "artifact": string;
-  "from"?: string;
-  "seat"?: string;
-  "version"?: string;
-}
-
-export interface StepAskBuildToolchain {
-  "language": string;
-  "recipe": string;
-  "version": string;
-}
-
 export interface StepAskBuild {
-  "artifacts": StepAskBuildArtifactsItem[];
+  "artifacts": AskArtifact[];
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch"?: Fetch;
-  "fetch"?: unknown;
   "fp"?: string;
   "module": string;
   "path"?: string;
   "publish"?: boolean;
-  "toolchain"?: StepAskBuildToolchain;
+  "toolchain"?: ToolchainUsed;
 }
 
 export interface StepAskCheck {
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
   "kept"?: boolean;
   "levels": string[];
   "packages"?: string[];
@@ -169,8 +181,7 @@ export interface StepAskCheck {
 
 export interface StepAskCompose {
   "dir": string;
-  /** what the build module fetches: the repository, commit and directory, as the indexer states it */
+  "fetch": Fetch;
-  "fetch": unknown;
   "package": string;
   "reader"?: string;
   /** the compose-candidate request */
@@ -197,6 +208,26 @@ export interface StepAsk {
   "v"?: number;
 }
 
+/** what a step answered, by the kind of ask: a build's artifacts, toolchain, imports and out-of-step modules; a check's fetch and levels; a compose's built, key and verdict; a declined ask's declined, needs and lacks. The fields of the kinds do not meet, so one layout holds the four */
+export interface StepResult {
+  "artifacts"?: BuiltArtifact[];
+  "built"?: boolean;
+  /** the holder declined the ask: its node lacks what the ask needs */
+  "declined"?: boolean;
+  "fetch"?: Fetch;
+  "imports"?: string[];
+  "key"?: string;
+  /** what the holder's node lacks of it */
+  "lacks"?: string[];
+  "levels"?: LevelAnswer[];
+  /** what the declined ask needs */
+  "needs"?: string[];
+  "out-of-step"?: string[];
+  "toolchain"?: ToolchainUsed;
+  /** the compose-candidate verdict (the composer's own layout) */
+  "verdict"?: unknown;
+}
+
 /** the toolchain a node reports */
 export interface Toolchain {
   /** when (RFC 3339 time) */
@@ -209,6 +240,13 @@ export interface Toolchain {
   "version": string;
 }
 
+/** the toolchain a build was made with: the language, the installed version and the build module's recipe */
+export interface ToolchainUsed {
+  "language": string;
+  "recipe": string;
+  "version": string;
+}
+
 /** is what current takes. */
 export interface CurrentInput {
 }