v0.1.0.dev6

Shared runtime compatibility and supported older consumer behavior are now explicit common contracts (R-SHARED-RUNTIME-COMPAT, C81-C83).

The additive Python API provides:

• Strict immutable consumer/runtime descriptions and deterministic, context-sensitive consumer binding IDs.
• Exact declared compatibility checks, including required commands and capabilities.
• Explicit or established-legacy binding selection, with refusal for missing, malformed, ambiguous or unsupported context.
• Conservative retention decisions that preserve consumer/active references and retain all assets when dependencies are unknown.
• Stable runtime-refusal codes preserved across ordinary copy, deepcopy and pickle reconstruction.

The dev4 public API floor, existing provider schemas/prompts and runtime bundle identities are preserved. No new dependency is introduced. See the API contract.

Hosts authenticate artifacts and compatibility evidence and own installation transactions, native adapters, configuration, authentication and execution. These pure APIs do not deploy a common launcher or certify a host's C81-C83 lifecycle. Codex adoption is separately reviewed; Claude and AGY maintainers receive pinned follow-up work through their existing proposal PRs. Existing users do not acquire a different host context merely by upgrading this library.

Local verification: 1,521 tests passed in both source and unpacked sdist on macOS ARM64/Python 3.12.13. Authoring/assets/API checks and all four installed-wheel drivers passed; the two rebuilt wheels were byte-identical. Final independent review and exact-head native CI evidence are recorded in PR #28.

This is a development prerelease. The published-event workflow verifies the exact tag on native macOS/Ubuntu with Python 3.12/3.14, then publishes its normalized sdist, rebuilt wheel and triad-release.json manifest. Consumers should verify that manifest and exact archive hashes before adoption.