Added

• Request body size cap (16 MB) — oversized POST /v1/chat/completions payloads return HTTP 413 (#14).
• Loopback Host header validation — requests to a loopback bind with an unexpected Host return HTTP 403 invalid_host, guarding against DNS-rebinding from browser-based clients (#14).
• HTTP server timeouts: headers 30s, request 120s, keep-alive 5s (#14).
• Deterministic contract + E2E test coverage using pi-ai's faux provider; added lifecycle and security tests (#14).
• Side-effect-labeled extension tool descriptions (gateway_start / gateway_stop note "Side effect: ..."; gateway_status notes "Read-only") (#14).
• pi-package keyword in package.json so the package is indexed by the pi.dev package gallery, which lists only npm packages tagged with that exact keyword.
• CHANGELOG.md. The release workflow extracts the version's section as the GitHub Release body.

Changed

• Migrated pi runtime dependencies from the deprecated @mariozechner/pi-* namespace to @earendil-works/pi-* at ^0.75.4 (latest mature version under the 7-day minimum-release-age policy). No public API changes.
• Supported OpenAI request parameters are forwarded to pi-ai; unsupported parameters (frequency_penalty, presence_penalty, response_format, seed, stop, top_p, user) are now rejected deterministically rather than silently ignored, so clients get an explicit error instead of unexpected output (#14).
• Centralized config security validation (validateGatewayConfigSecurity) and assert the bound address after listen() (#14).
• Extension daemon: log to a file, sanitize the detached child's environment, and cap the footer health-probe response body (#14).
• Contract test validates the OpenAI error envelope on non-200 responses and on mid-stream error frames (which correctly omit the trailing data: [DONE] per OpenAI's mid-stream error convention). CI passes without provider auth.
• Publish workflow's canary job gated on vars.ENABLE_CANARY == 'true'; enabled per push to main once npm trusted-publishing is configured.

Fixed

• Hardened auth/bind invariants and OpenAI error envelopes across the request path (#14, closes #6–#13).
• Contract test no longer fails when no provider auth is configured (CI environment).

Security

• Loopback Host-header guard prevents DNS-rebinding access from browser-based clients on the same machine (#14).