modelcontextprotocol / modelcontextprotocol/servers
Fail closed on unknown tool/resource/prompt declarations in server manifests
Nobody has claimed this yet.
- Dominant language
- TypeScript
- Stars
- 90.5k
- Forks
- 11.7k
- Avg merge
- 2d 2h
- Merged PRs (30d)
- 5
Description
Problem
Unknown tool/resource/prompt declarations can be silently ignored, masking configuration mistakes.
Why now
Reference servers should model strict protocol contracts and safe defaults.
Current behavior is insufficient
Permissive handling of unknown declarations can hide operator misconfiguration until runtime.
Expected behavior
Server manifest loading should fail closed when unknown declarations are present.
Acceptance criteria
- Unknown declaration keys fail startup deterministically.
- Error output identifies offending declaration path(s).
- Strict validation applies to tool/resource/prompt declaration sections.
Validation
- Add fixtures with unknown declarations and assert deterministic failures.
- Verify valid manifests continue to pass unchanged.
Codepaths
src/everythingsrc/filesystemsrc/fetchsrc/git
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by tracing server manifest loading in src/everything, src/filesystem, src/fetch, and src/git. Add fixtures containing unknown tool, resource, and prompt declarations, then run the existing validation checks to confirm deterministic startup failures and offending declaration paths. Done means valid manifests still pass unchanged.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- typescript
- Domain
- api, backend, testing
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100