fix(mcp): stop Sentry noise for unknown MCP server names

[kentcdodds]

Summary

Sentry KODY-CLOUDFLARE-29 fired when mcp_server_reconnect was called with a server name that is not saved (recipe-keeper; only ha existed). That is a routine caller mistake (stale name / typo), not a platform defect.

resolveMcpServerSetting threw a plain Error, so MCP observability reported it to Sentry. This PR throws McpCallerError instead (same pattern as missing packages/runs), so these stay on mcp-event logs and out of Sentry.

Changes

• Blank and unknown server identifiers in resolveMcpServerSetting → McpCallerError
• Unit tests for unknown name, blank id, and happy-path id/name resolution

Test plan

• shared.node.test.ts (3 tests)
• CI validate green

System recap — composes existing primitives (low risk)

Mode: recap · Base: main @ 405751b2 · Head: cursor/sentry-triage-kody-cloudflare-29-215a

Classification: composes — reuses existing McpCallerError so caller-resolvable MCP server lookup failures stay off Sentry; no new primitives or contracts.

Primitives touched

Primitive	Group	Impact
mcp-client-servers	assistant	composes — unknown/blank server lookup throws McpCallerError

System map

Unknown MCP server names from reconnect/refresh/remove/set-enabled now classify as caller errors instead of platform exceptions.

Legend: green = composes (wiring only) · amber = extended by this PR · red = new primitive · gray = context (unchanged, included only when an edge crosses it).

flowchart LR
	mcpClientServers["mcp-client-servers<br/>MCP client servers"]:::touched
	mcpObs["mcp-server<br/>MCP endpoint"]:::untouched
	mcpClientServers -->|"McpCallerError skips Sentry"| mcpObs
	classDef touched fill:#1a7f37,color:#fff
	classDef extended fill:#9a6700,color:#fff
	classDef added fill:#cf222e,color:#fff
	classDef untouched fill:#57606a,color:#fff

Loading

Before / after

Path	Before	After
Unknown / blank server in resolveMcpServerSetting	Error → Sentry issue	McpCallerError → mcp-event only

  

Summary by CodeRabbit

• Bug Fixes
  • Improved validation for missing or blank MCP server selections, now returning caller-specific errors.
  • Added clearer caller-facing errors when an MCP server cannot be found (including known saved server guidance).
  • Server names are resolved consistently regardless of capitalization.
• Tests
  • Added Vitest coverage for resolving MCP server settings by ID and case-insensitive name, including invalid and unmatched inputs.

[coderabbitai]

📝 Walkthrough

Walkthrough

resolveMcpServerSetting now classifies blank and unknown server inputs as McpCallerError. New tests cover error messages, skipped lookups, direct ID resolution, and case-insensitive name fallback.

Changes

MCP caller error handling

Layer / File(s)	Summary
Classify invalid server inputs packages/worker/src/mcp/capabilities/mcp-servers/shared.ts	resolveMcpServerSetting throws McpCallerError for blank input and unresolved server IDs or names.
Test server resolution and errors packages/worker/src/mcp/capabilities/mcp-servers/shared.node.test.ts	Mocked settings services verify validation behavior, missing-server messages, direct ID lookup, and case-insensitive name fallback.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related PRs

• kentcdodds/kody#662: Introduces the MCP server setting resolution logic covered by this change.
• kentcdodds/kody#919: Introduces related McpCallerError behavior and Sentry exclusion.
• kentcdodds/kody#922: Implements related McpCallerError detection and Sentry filtering.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly matches the main change: unknown MCP server names no longer generate Sentry noise.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch cursor/sentry-triage-kody-cloudflare-29-215a

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[github-actions]

🔎 Preview deployed: https://kody-pr-959.kody-a99.workers.dev

Worker: kody-pr-959
D1: kody-pr-959-db
KV: kody-pr-959-oauth-kv

Mocks:

• cloudflare: https://kody-pr-959-mock-cloudflare.kody-a99.workers.dev/__mocks (kody-pr-959-mock-cloudflare)

[coderabbitai]

🧹 Nitpick comments (1)

packages/worker/src/mcp/capabilities/mcp-servers/shared.node.test.ts (1)

65-65: 📐 Maintainability & Code Quality | 🔵 Trivial | ⚡ Quick win

Also assert that the list lookup is skipped for blank input.

The test guards getMcpServerSettingById, but the blank-input path should avoid both service calls.

Suggested assertion

  expect(mockModule.getMcpServerSettingById).not.toHaveBeenCalled()
+ expect(mockModule.listMcpServerSettings).not.toHaveBeenCalled()

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@packages/worker/src/mcp/capabilities/mcp-servers/shared.node.test.ts` at line
65, Update the blank-input test alongside the existing getMcpServerSettingById
assertion to also verify that the list lookup service is not called. Keep the
test focused on confirming both service calls are skipped when the input is
blank.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@packages/worker/src/mcp/capabilities/mcp-servers/shared.node.test.ts`:
- Line 65: Update the blank-input test alongside the existing
getMcpServerSettingById assertion to also verify that the list lookup service is
not called. Keep the test focused on confirming both service calls are skipped
when the input is blank.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: dfd1ae9f-17d6-4d66-becd-74d6ee68c578

📥 Commits

Reviewing files that changed from the base of the PR and between 405751b and e7f2958.

📒 Files selected for processing (2)

• packages/worker/src/mcp/capabilities/mcp-servers/shared.node.test.ts
• packages/worker/src/mcp/capabilities/mcp-servers/shared.ts