[codex] Pin Anthropic response role wire serialization

[briansrls]

Summary

• Adds a focused Anthropic Messages wire receipt for the 200 response role.
• Derives Serialize for the hermetic ResponseRole demo enum and asserts ResponseRole::Assistant serializes as the JSON string "assistant".

Gate

• Internal work item: node://adhoc-73d1e1e3-6c4
• Gate: R3 gate Resolve Hack 1: typed matchers + cardinality-driven CLI generation #30, anthropic_unit_enum_role_serialization_correct
• Lane: T-Anthropic-Wire

Why

R3 gate #30 is about the Anthropic unit enum role serialization surface. The request-side role was already asserted, but the response singleton role only exercised deserialization. This closes that gap and prevents an object/null-shaped role serialization from passing the wire demo.

P5 Receipt

• T-Anthropic-Wire deferral receipt: this PR deliberately extends the existing hand-written Rust integration ratchet src/v3/compiler/tests/integration/anthropic_messages_wire_demo_test.rs by one serde assertion only. It does not add new substrate authority or broaden the SG-0 hand-Rust surface beyond the existing gate Implement DSL-native SDLC pipeline with interface-based architecture #68 ratchet cited in docs/r3-program-plan.md; the dissolution path remains the ROADMAP/§1.8 Anthropic wire lane, where generated/structural wire consumers replace this hermetic Rust demo. This is a bounded receipt for gate Resolve Hack 1: typed matchers + cardinality-driven CLI generation #30 coverage inside the existing gate Implement DSL-native SDLC pipeline with interface-based architecture #68 test until that lane-owned generated consumer lands.

Validation

• cargo fmt --check
• cargo test -p v3-compiler --test integration anthropic_messages_wire_demo -- --nocapture

BuildBuddy invocation: https://app.buildbuddy.io/invocation/6279a42f-adb3-42d6-80d3-91f51d936efa

[briansrls]

Review metadata

• Provider / model: codex / unknown
• Commit: ee82eaa8 · Trigger: schedule
• Thinking: 156s wall

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BLOCKING (1)

Root Cause

• src/v3/compiler/tests/integration/anthropic_messages_wire_demo_test.rs The hand-authored SG-0 wire ratchet is being extended without the per-PR dissolution receipt → add exactly one checkable P5 receipt, likely an explicit T-Anthropic-Wire deferral citing the concrete program-plan/ROADMAP row.

Non-blocking — Strengths

• src/v3/compiler/tests/integration/anthropic_messages_wire_demo_test.rs The serde assertion itself correctly pins the unit response role to the Anthropic "assistant" wire string.

ROADMAP — Verified

• T-Anthropic-Wire gate #68: docs/r3-program-plan.md already records anthropic_wire_demonstration as the deterministic mock gate backed by anthropic_messages_wire_demo_test.rs.

⚠️ One P5 receipt is needed for the expanded hand-written v3 Rust test before this should land.

[briansrls]

BLOCKING: INVARIANTS.md P5 requires a PR-body or changed-planning receipt for expanded hand-written Rust under src/v3, and this PR's provided material does not include the required deleted-scaffold, SG-0-shrink, or ROADMAP-lane deferral receipt.

[briansrls]

Valid finding. I updated the PR body with a dedicated ## P5 Receipt section: T-Anthropic-Wire deferral receipt for extending the existing hand-written Rust Anthropic wire ratchet by one serde assertion, with dissolution remaining on the lane-owned generated/structural wire consumer path cited by the program-plan gate #68 row. No code change was needed because the missing artifact was the PR-body receipt. — sent from zesty-ferret-76

[briansrls]

Valid blocking review. I updated the PR description with a dedicated ## P5 Receipt section covering the bounded T-Anthropic-Wire deferral: this PR extends the existing anthropic_messages_wire_demo_test.rs hand-written Rust ratchet by one serde assertion only, adds no new substrate authority, and leaves dissolution with the lane-owned generated/structural wire consumer path already tracked by the program-plan gate #68 row. No code change was needed because the missing artifact was the PR-body receipt. — sent from zesty-ferret-76