artifact-projection-read

artifact-projection-read

This is an OpenCode-native Skill projection generated from the portable capability contract. It is adapter-owned output, not a legacy compatibility Skill copy.

Source

• Portable source: capabilities/artifact-projection-read.md
• Runtime check: adapters/opencode/bin/preflight.sh capability-info artifact-projection-read
• Bootstrap: adapters/opencode/AGENTS.md

Use

1. Read capabilities/artifact-projection-read.md for the runtime-neutral contract.
2. Run adapters/opencode/bin/preflight.sh capability-info artifact-projection-read.
3. Obey the reported status:
   • instruction-only: use this Skill as OpenCode guidance plus explicit preflight guards.
   • tool-contract: report the named tool_contract, run any tool_contract_check, and obey runtime_surface / fallback before claiming full support.
   • unsupported: stop or use the reported fallback.

Shape

• Identifier: artifact-projection-read
• Invocation class: model-support
• Supported modes: none
• Argument shape: one JSON read request on stdin
• Portable meaning: Read-only lookup of Cairn artifact projections through the canonical W3a contract.

Portable Contract

• Invocation semantics: Run utilities/cairn-artifact-read.sh with exactly one JSON object on stdin. The command emits exactly one JSON value on stdout and diagnostics only on stderr. Set CAIRN_ROOT to the checkout containing W3a commit 1fa0d99e4b714b5ce305f78c8f7c7773255e8f87, provide the read-only CAIRN_READ_ENDPOINT, and set CAIRN_READ_TOKEN only when the service requires it. The request is validated by W3a's validateReadOptions, then passed to W3a's ArtifactProjectionClient and HttpReadTransport without local query, cursor, or authorization interpretation. The token is never printed. This capability is intentionally narrower than browse/search fallback paths. It has no write, ingest, apply, activate, deactivate, migrate, or namespace switch operation and never accepts a database URL. Missing or mismatched W3a sources fail closed using W3a's imported contract errors. If the W3a query fails, Hearting does not take ownership of a fallback; the caller may use the separately owned browse/search or memory paths. Hearting may add a separate hearting_verification_display field to a successful read response. It joins only exact stable IDs and locally verified artifact revisions, and it preserves every W3a request, cursor, authorization, row, and error result. Verification verdict, operational completion, and required-input observation remain distinct. Missing or stale local evidence is displayed as unresolved while the successful remote read stays successful. This field is a read-time projection: it does not create a new input, gate, service, verification round, or durable sidecar, and it never changes source report or verdict bytes.

Projected Portable Details

Artifact Ownership

The command is read-only and owns no artifact mutation. Generated runtime projections must be produced from this portable file and the manifest. The Hearting bridge imports W3a request.ts, client.ts, and errors.ts; it must not copy their request fields, error names, retry policy, or exit table.

Role Requirements

The acting agent may select and invoke this read-only support capability while another capability remains the primary owner of the task. It must not broaden the request, interpret projection results as permission to mutate, or treat a failed projection read as ownership of the external fallback paths.

Guard Requirements

• Accept no command option, database URL, write credential, mutation key, or namespace activation/switch operation.
• Emit exactly one JSON object on stdout for success and failure. Any process diagnostic belongs only on stderr and must not contain a token, endpoint credential, database URL, or response body.
• Treat the imported 17-code W3a error order as the sole exit mapping: the corresponding exits are injective 2..18.
• Verify that the required W3a D-41 correction commit is an ancestor of the selected Cairn checkout before importing its runtime modules.
• When W3a modules cannot be imported, fail closed with the public D-41 INTERNAL_FAILURE code and exit 18; never expose private bootstrap codes.

Portable Procedure

1. Pipe one read request object to utilities/cairn-artifact-read.sh.
2. Parse the single stdout object. On a non-zero exit, use its typed error.code; do not infer meaning from stderr prose.
3. When the projection is unavailable or rejected, retain flat browse, rg, and memory artifact-pointer recall as additive external fallbacks. This capability does not own or replace those paths.

Portable procedure and reference documents are owned under capabilities/artifact-projection-read/references/ when present. Claude, Codex, and OpenCode Skill bodies are generated projections of this capability and use the same logical procedure read-set.

Workflow Evidence

• For workflow state: adapters/opencode/bin/preflight.sh status [cwd] [session-id] and adapters/opencode/bin/preflight.sh prompt-signal [cwd] [session-id]

Do not use legacy compatibility Skill files or non-native adapter Skill files as OpenCode-native source. Those files are compatibility/reference surfaces only.