feat(plugin-mcp): allow external plugins to extend mcp plugin by AlessioGr · Pull Request #16245 · payloadcms/payload

AlessioGr · 2026-04-10T20:57:52Z

Plugins can now extend plugin-mcp (e.g. inject custom MCP tools). A plugin finds plugin-mcp by slug via config.plugins, accesses its options, and pushes tools directly into options.mcp.tools. Because plugin-mcp uses a high priority (runs last), the injected tools are available when it builds the MCP server.

Also exports MCPPluginConfig type so external plugins can type the options object when injecting tools. Since it wasn't exported before, I took the opportunity to rename PluginMCPServerConfig => MCPPluginConfig. This is simpler and more consistent with type from our other plugins

To see the specific tasks where the Asana app for GitHub is being used, see below:
- https://app.asana.com/0/0/1214013522421643

AlessioGr · 2026-04-10T21:00:35Z

    return config
  }
+
+  plugin.slug = '@payloadcms/plugin-mcp'


This is the only change in this PR other than renaming the type

github-actions · 2026-04-10T21:10:33Z

📦 esbuild Bundle Analysis for payload

This analysis was generated by esbuild-bundle-analyzer. 🤖

Meta File	Out File	Size (raw)	Note
packages/next/meta_index.json	esbuild/index.js	984.34 KB	✅ No change
packages/payload/meta_index.json	esbuild/index.js	1.39 MB	⚠️ +10.09 KB (+0.7%)
packages/payload/meta_shared.json	esbuild/exports/shared.js	191.27 KB	✅ No change
packages/richtext-lexical/meta_client.json	esbuild/exports/client_optimized/index.js	288.93 KB	✅ No change
packages/ui/meta_client.json	esbuild/exports/client_optimized/index.js	1.18 MB	✅ No change
packages/ui/meta_shared.json	esbuild/exports/shared_optimized/index.js	16.32 KB	✅ No change

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Details

Next to the size is how much the size has increased or decreased compared with the base branch of this PR.

‼️: Size increased by 20% or more. Special attention should be given to this.
⚠️: Size increased in acceptable range (lower than 20%).
✅: No change or even downsized.
🗑️: The out file is deleted: not found in base branch.
🆕: The out file is newly found: will be added to base branch.

…sibility

github-actions · 2026-04-15T19:00:10Z

🚀 This is included in version v3.83.0

…dcms#16245) Plugins can now extend plugin-mcp (e.g. inject custom MCP tools). A plugin finds plugin-mcp by slug via `config.plugins`, accesses its options, and pushes tools directly into `options.mcp.tools`. Because plugin-mcp uses a high priority (runs last), the injected tools are available when it builds the MCP server. Also exports `MCPPluginConfig` type so external plugins can type the options object when injecting tools. Since it wasn't exported before, I took the opportunity to rename `PluginMCPServerConfig` => `MCPPluginConfig`. This is simpler and more consistent with type from our other plugins

commit

024191a

github-actions Bot added the created-by: Payload team label Apr 10, 2026

rename

4681a7e

AlessioGr commented Apr 10, 2026

View reviewed changes

AlessioGr enabled auto-merge (squash) April 10, 2026 21:01

AlessioGr added 2 commits April 14, 2026 09:28

Merge remote-tracking branch 'origin/main' into feat/plugin-mcp-exten…

99ba151

…sibility

use new definePlugin api

16f2b36

AlessioGr requested a review from paulpopus April 14, 2026 16:36

AlessioGr added 2 commits April 14, 2026 09:43

update test

5331e9b

update config

2c6a88c

paulpopus approved these changes Apr 14, 2026

View reviewed changes

AlessioGr merged commit ac4fc31 into main Apr 14, 2026
330 of 332 checks passed

AlessioGr deleted the feat/plugin-mcp-extensibility branch April 14, 2026 17:46

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feat(plugin-mcp): allow external plugins to extend mcp plugin#16245

feat(plugin-mcp): allow external plugins to extend mcp plugin#16245
AlessioGr merged 6 commits into
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Meta file: packages/next/meta_index.json, Out file: esbuild/index.js

Meta file: packages/payload/meta_index.json, Out file: esbuild/index.js

Meta file: packages/payload/meta_shared.json, Out file: esbuild/exports/shared.js

Meta file: packages/richtext-lexical/meta_client.json, Out file: esbuild/exports/client_optimized/index.js

Meta file: packages/ui/meta_client.json, Out file: esbuild/exports/client_optimized/index.js

Meta file: packages/ui/meta_shared.json, Out file: esbuild/exports/shared_optimized/index.js

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📦 esbuild Bundle Analysis for payload

Meta file: packages/next/meta_index.json, Out file: esbuild/index.js

Meta file: packages/payload/meta_index.json, Out file: esbuild/index.js

Meta file: packages/payload/meta_shared.json, Out file: esbuild/exports/shared.js

Meta file: packages/richtext-lexical/meta_client.json, Out file: esbuild/exports/client_optimized/index.js

Meta file: packages/ui/meta_client.json, Out file: esbuild/exports/client_optimized/index.js

Meta file: packages/ui/meta_shared.json, Out file: esbuild/exports/shared_optimized/index.js

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