fix: preserve stateful MCP extension capabilities

[lloydrichards]

Type

• Bug Fix

Description

There was a bit of an oversight when implementing the #7265 where the server extension capabilities we're not being correctly passed into the McpSchema.InitializeResult. All the plumbing was already there, just missing the field.

I also added this to the v2024 protocol just for posterity sake as well as cleaned up the era tests to make sure this is all regression proof.

Related

• Closes McpServer drops capabilities.extensions on stateful protocol revisions (2025-03-26 / 2025-06-18 / 2025-11-25) #8663
• Closes EFF-1669

[changeset-bot]

🦋 Changeset detected

Latest commit: 67b015b

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 31 packages

Name	Type
effect	Patch
@effect/opentelemetry	Patch
@effect/vitest	Patch
@effect/ai-anthropic	Patch
@effect/ai-openai-compat	Patch
@effect/ai-openai	Patch
@effect/ai-openrouter	Patch
@effect/ai-typesafe	Patch
@effect/atom-react	Patch
@effect/atom-solid	Patch
@effect/atom-vue	Patch
@effect/platform-browser	Patch
@effect/platform-bun	Patch
@effect/platform-deno	Patch
@effect/platform-node-shared	Patch
@effect/platform-node	Patch
@effect/sql-clickhouse	Patch
@effect/sql-d1	Patch
@effect/sql-libsql	Patch
@effect/sql-mssql	Patch
@effect/sql-mysql2	Patch
@effect/sql-pg	Patch
@effect/sql-pglite	Patch
@effect/sql-sqlite-bun	Patch
@effect/sql-sqlite-do	Patch
@effect/sql-sqlite-node	Patch
@effect/sql-sqlite-react-native	Patch
@effect/sql-sqlite-wasm	Patch
@effect/docgen	Patch
@effect/doctest	Patch
@effect/openapi-generator	Patch

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[github-actions]

Bundle Size Analysis

Generated from PR build output; treat the content below as untrusted.

File Name	Current Size	Previous Size	Difference
arbitrary-combinators.ts	38.90 KB	38.90 KB	0.00 KB (0.00%)
basic.ts	7.04 KB	7.04 KB	0.00 KB (0.00%)
batching.ts	10.13 KB	10.13 KB	0.00 KB (0.00%)
brand.ts	6.72 KB	6.72 KB	0.00 KB (0.00%)
cache.ts	10.84 KB	10.84 KB	0.00 KB (0.00%)
config.ts	22.15 KB	22.15 KB	0.00 KB (0.00%)
differ.ts	21.29 KB	21.29 KB	0.00 KB (0.00%)
http-client.ts	22.27 KB	22.27 KB	0.00 KB (0.00%)
http-router.ts	33.52 KB	33.52 KB	0.00 KB (0.00%)
logger.ts	11.08 KB	11.08 KB	0.00 KB (0.00%)
metric.ts	9.02 KB	9.02 KB	0.00 KB (0.00%)
optic.ts	6.95 KB	6.95 KB	0.00 KB (0.00%)
pubsub.ts	15.16 KB	15.16 KB	0.00 KB (0.00%)
queue.ts	12.08 KB	12.08 KB	0.00 KB (0.00%)
schedule.ts	11.18 KB	11.18 KB	0.00 KB (0.00%)
schema-bigdecimal.ts	13.73 KB	13.73 KB	0.00 KB (0.00%)
schema-binary.ts	39.92 KB	39.92 KB	0.00 KB (0.00%)
schema-class.ts	21.03 KB	21.03 KB	0.00 KB (0.00%)
schema-fromJsonSchemaDocument.ts	32.06 KB	32.06 KB	0.00 KB (0.00%)
schema-representation-roundtrip.ts	27.24 KB	27.24 KB	0.00 KB (0.00%)
schema-string-transformation.ts	14.46 KB	14.46 KB	0.00 KB (0.00%)
schema-string.ts	11.99 KB	11.99 KB	0.00 KB (0.00%)
schema-template-literal.ts	16.05 KB	16.05 KB	0.00 KB (0.00%)
schema-toArbitrary.ts	38.44 KB	38.44 KB	0.00 KB (0.00%)
schema-toCodeDocument.ts	25.26 KB	25.26 KB	0.00 KB (0.00%)
schema-toCodecJson.ts	20.21 KB	20.21 KB	0.00 KB (0.00%)
schema-toEquivalence.ts	20.41 KB	20.41 KB	0.00 KB (0.00%)
schema-toFormatter.ts	20.54 KB	20.54 KB	0.00 KB (0.00%)
schema-toJsonSchemaDocument.ts	25.00 KB	25.00 KB	0.00 KB (0.00%)
schema-toRepresentation.ts	20.50 KB	20.50 KB	0.00 KB (0.00%)
schema.ts	20.25 KB	20.25 KB	0.00 KB (0.00%)
stm.ts	13.08 KB	13.08 KB	0.00 KB (0.00%)
stream.ts	9.98 KB	9.98 KB	0.00 KB (0.00%)