Contract Builder

Converts planning artifacts into a single execution handshake: execution-contract.md. Load the baseline with ssf runtime asset read templates/execution-contract.md.

Read before generating: .spec-superflow.yaml (especially dp_0_decisions), proposal.md, specs/, design.md, tasks.md, then load docs/artifact-contract.md with ssf runtime asset read docs/artifact-contract.md.

Artifact Language

Read artifact_language=<concrete-language> from dp_0_decisions. Generate execution-contract.md in the same language as that resolved value and the approved planning artifacts. Preserve required schema keywords and code identifiers verbatim; language consistency applies to explanatory prose and headings. If the concrete artifact language is missing or still auto, route back to workflow-start before writing the contract instead of guessing or silently defaulting to English.

Artifact Mapping

Cross-Check: Requirement Coverage

Before finalizing:

1. List every SHALL/MUST from specs/
2. Verify each is reflected in Approved Behavior, has a test obligation, and appears in at least one batch
3. Flag unmapped requirements in Escalation Rules
4. Note cross-batch dependencies

Contract Structure

Must make obvious: approved behavior, out-of-scope, constraints, batches, test obligations, review gates, and conditions that force a rewind to planning. Prefer compression over repeating planning details.

Approval Model (DP-3)

After drafting: summarize handoff rules, identify ambiguity, flag unmapped requirements, ask user to approve explicitly. After approval:

ssf state set <change-dir> dp_3_result "approved: <summary>"
ssf state set <change-dir> dp_3_timestamp $(date -u +%Y-%m-%dT%H:%M:%SZ)

DP-3 is a hard gate — no implementation without this record.

Stale Contract Detection

Refresh if: scope changed in proposal, requirements changed in specs, constraints changed in design, batches changed materially in tasks, or the contract no longer matches intent.

Hotfix Mode

Generate a minimal contract only for a legacy Hotfix: Intent Lock (one sentence), Task List (numbered), Approval Gate (DP-3). Skip Scope Fence, Build Rules, Review Gates, Test Evidence. Still requires DP-3 approval. Quick direct execution and direct incident Hotfix do not invoke this skill; they use the signed receipt and finish with test_result: pass instead.

Guardrails

• Do not continue to implementation if ambiguity remains
• Do not approve the contract on the user's behalf
• Do not skip the contract because planning docs look complete
• Flag unmapped requirements; do not silently drop them

Post-Generation

Run ssf state init <change-dir> to create .spec-superflow.yaml with hashes.

For a legacy Hotfix, after writing the minimal contract, run ssf state init <change-dir> or ssf state rebuild <change-dir> so contract_hash is recorded. DP-3 remains mandatory before build.

Exception Handling

• Parse failures: Report specific file and section. Suggest re-running spec-writer.
• Missing files: List every missing artifact. Route back to spec-writer.
• User interruption: Re-read all artifacts on resume; check contract staleness via content comparison.
• Validation failure: Flag unmapped requirements in Escalation Rules and approval summary.