[dependabot]

Bumps tower-mcp from 0.23.2 to 0.25.0.

Release notes

Sourced from tower-mcp's releases.

tower-mcp-v0.25.0

Upgrade notes

• HTTP session status codes (breaking). On the 2025 session path, a request for an unknown, expired, terminated or other-principal session now gets HTTP 404, and a request missing a required Mcp-Session-Id gets HTTP 400, on POST, GET and DELETE. The JSON-RPC bodies (-32005, -32006) are unchanged. Spec clients (rmcp, the TypeScript and Python SDKs) now re-initialize on expiry; anything that expected HTTP 200 for these must accept 404/400. DELETE of an unknown id is 404 instead of 200, and a DELETE now removes a session held only in a shared SessionStore (#1591, #1597).
• McpClientBuilder is no longer UnwindSafe / RefUnwindSafe, because it can hold the new trace_context_provider closure (#1595).
• HTTP client redirects. The default client follows only 307 and 308; a 301, 302 or 303 now fails with a clear error instead of turning the POST into a bodyless GET. Configure the final URL for an endpoint that redirects (#1592).
• output_schema_for::<T>() describes T as it serializes. An always-written Option field is now required (nullable), and serialize-side renames apply. With schema-validation, structured content that omits such a field now fails output validation (#1593).
• Request ids written as integral floats (1.0) are accepted and answered with the integer (#1593).
• Diagnostics. HTTP and JWKS transport errors and logs no longer include URLs, response bodies, redirect targets or scope values; they report safe categories, status codes and known OAuth error codes. HttpStatusDetails still carries structured status data (#1586).
• stdio. On Linux, when stdin and stdout are pipes, the server transports use non-blocking I/O on a private file description instead of tokio's blocking pool, so a server exits after shutdown even if the client keeps stdin open. StdioPipes::Shared extends this to macOS pipes and sockets; StdioPipes::Blocking restores the old path (#1596).
• ChildProcessConnection::shutdown sends SIGTERM before SIGKILL, so it can take up to 10 s instead of 5 s (#1593).
• New APIs:
  • replace_all on the dynamic registries (one list_changed, returns a RegistryChange), check_schema, and ResourceTemplateBuilder::handler_with_context (#1584);
  • McpClientBuilder::trace_context_provider and the guides::tracing OpenTelemetry guide (#1595);
  • the guides::local_runtime guide for !Send runtimes, with examples/lua-tools as a worked example (#1584, #1587).

Bug Fixes

• Redact sensitive HTTP and JWKS diagnostics (#1586)
• [breaking] http: Answer an unknown session id with 404 and a missing session id with 400 (#1591)
• client: Keep x-mcp-header mappings across tools/list pages and follow only 307/308 redirects (#1592)
• Accept integral-float request ids, build outputSchema for the serialize contract, SIGTERM before SIGKILL in childproc (#1593)
• http: DELETE removes a session that lives only in the shared SessionStore (#1597)

Features

• Batch registry replace, check_schema, template context handler, !Send guide (#1584)
• client: Send W3C trace context on each request, and document OpenTelemetry linking (#1595)
• stdio: Serve piped stdio without tokio's blocking pool, so shutdown no longer waits on stdin (#1596)

tower-mcp-types-v0.25.0

Bug Fixes

• Accept integral-float request ids, build outputSchema for the serialize contract, SIGTERM before SIGKILL in childproc (#1593)

tower-mcp-macros-v0.25.0

No release notes provided.

tower-mcp-v0.24.0

Upgrade notes

• Error codes (breaking). An unknown, disabled or filtered tool or prompt is now answered -32602 (Invalid params) on every protocol revision, as every supported spec revision specifies, instead of -32601 (Method not found). DenialBehavior::NotFound produces -32602 too. On the 2026-07-28 HTTP path, a handler's -32602 stays in-band at HTTP 200 instead of becoming HTTP 400, which clients read as "fall back to initialize". Code or tests that match -32601 for these cases must change (#1560).
• HTTP client errors. A 429 or 5xx no longer disconnects HttpClientTransport; only 404 and 410 without a session close it. Failed requests carry httpStatus, retryAfter and wwwAuthenticate in the error data, readable with HttpStatusDetails::from_error (#1559, #1565). Any 404 on a 2025-11-25 session request now re-initializes the session (#1565).
• Client sessions. A failed initialize() sends a DELETE for the session the server issued (#1570). ClientTransport gains end_session, with a default no-op.
• Origin and Host. A request with more than one Origin header gets 403, and userinfo, query, fragment or invalid-port origins are no longer treated as localhost. WebSocketTransport validates Host with the same defaults as HTTP (#1566).
• structuredContent. An explicit "structuredContent": null now decodes as Some(Value::Null) instead of None (#1568).
• OAuth client. With no explicit, challenge or protected-resource scopes, the authorization URL no longer lists the authorization server's scopes_supported. A confidential dynamic registration that returns no client_secret is an error at registration (#1569).
• stdio. A request the client cancels is no longer answered (#1552). When drain_timeout expires, in-flight handlers are cancelled and then aborted (#1562).

Bug Fixes

... (truncated)

Commits

• 80c7456 chore: release (#1582)
• 202536a fix(http): DELETE removes a session that lives only in the shared SessionStor...
• cb40471 feat(stdio): serve piped stdio without tokio's blocking pool, so shutdown no ...
• 3002eb2 feat(client): send W3C trace context on each request, and document OpenTeleme...
• 39debc9 test: validate every wire frame against the published MCP schema (#1594)
• 2f57810 fix: accept integral-float request ids, build outputSchema for the serialize ...
• 9fcb240 fix(client): keep x-mcp-header mappings across tools/list pages and follow on...
• f394fa4 fix(http)!: answer an unknown session id with 404 and a missing session id wi...
• 8ea3d97 docs(examples): serve Lua-defined tools with the embedder APIs from #1584 (#1...
• da93edd feat: batch registry replace, check_schema, template context handler, !Send g...
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)