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main is currently in pre mode so this branch has prereleases rather than normal releases. If you want to exit prereleases, run changeset pre exit on main.

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Releases

@modelcontextprotocol/client@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.

@modelcontextprotocol/codemod@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.

• #2412 ef120b2 Thanks @felixweinberger! - v1-to-v2 migration fixes from continued real-world migrations (codemod iterations 5).

@modelcontextprotocol/core@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.

@modelcontextprotocol/express@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.
• Updated dependencies [f172626, 3c7ddaf]:
  • @modelcontextprotocol/server@2.0.0-beta.2

@modelcontextprotocol/fastify@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.
• Updated dependencies [f172626, 3c7ddaf]:
  • @modelcontextprotocol/server@2.0.0-beta.2

@modelcontextprotocol/hono@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.
• Updated dependencies [f172626, 3c7ddaf]:
  • @modelcontextprotocol/server@2.0.0-beta.2

@modelcontextprotocol/node@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.
• Updated dependencies [f172626, 3c7ddaf]:
  • @modelcontextprotocol/server@2.0.0-beta.2

@modelcontextprotocol/server@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.

• #2399 3c7ddaf Thanks @felixweinberger! - Return HTTP 400 for a MissingRequiredClientCapabilityError (-32021) produced after dispatch. The spec mandates 400 Bad Request for this error with no condition on where it arose, but only the pre-dispatch capability gate honored that; the post-handler emission — the input_required gate rejecting an embedded request whose required capability the caller did not declare — surfaced in-band on HTTP 200. The JSON-RPC error body is unchanged, every other error code (including a handler relaying a downstream peer's -32020/-32022) keeps the origin-keyed in-band behavior, and the mapping only applies while the response is uncommitted: an exchange that already streamed — or one hosted with responseMode: 'sse', which opens its stream at dispatch end — keeps its committed 200 and carries the error in-stream.

@modelcontextprotocol/server-legacy@2.0.0-beta.2

Patch Changes

• #2405 f172626 Thanks @mattzcarey! - Ship CommonJS builds alongside ESM. Each package now emits both .mjs/.d.mts
  and .cjs/.d.cts (via tsdown format: ['esm', 'cjs']), and its exports map
  adds a require condition so require('@modelcontextprotocol/…') works from
  CommonJS consumers. Output extensions are normalized across all packages
  (@modelcontextprotocol/core moves from .js/.d.ts to .mjs/.d.mts); the
  public import paths are unchanged.

@modelcontextprotocol/core-internal@2.0.0-beta.1

Patch Changes

• #2399 3c7ddaf Thanks @felixweinberger! - Return HTTP 400 for a MissingRequiredClientCapabilityError (-32021) produced after dispatch. The spec mandates 400 Bad Request for this error with no condition on where it arose, but only the pre-dispatch capability gate honored that; the post-handler emission — the input_required gate rejecting an embedded request whose required capability the caller did not declare — surfaced in-band on HTTP 200. The JSON-RPC error body is unchanged, every other error code (including a handler relaying a downstream peer's -32020/-32022) keeps the origin-keyed in-band behavior, and the mapping only applies while the response is uncommitted: an exchange that already streamed — or one hosted with responseMode: 'sse', which opens its stream at dispatch end — keeps its committed 200 and carries the error in-stream.