[MCP] detectVerbs manufactures create_* tools for every Resource subclass, including built-in login

[kylebernhardy]

Found during review of #1943.

Problem

detectVerbs (components/mcp/tools/application.ts:694) tests for verb presence without comparing against the base prototype:

create: typeof p.post === 'function' || typeof p.update === 'function',

resources/Resource.ts defines async post() on Resource.prototype, so every class extending Resource reports create: true — whether or not its author implemented post.

The codebase already has the correct version of this check a file away, in components/mcp/toolRegistry.ts (hasClassLevelVerbs), which does compare:

post: (typeof prototype.post === 'function' && prototype.post !== resourcePrototype.post) || typeof prototype.update === 'function',

Its own comment says it "mirrors resources/openApi.ts" — so OpenAPI and MCP's toolRegistry agree, and detectVerbs is the odd one out.

Impact

Every exported Resource gets a spurious create_* tool advertised to the model, described as "Creates a new X record. Runtime RBAC (allowCreate) enforces per-record access at call time." Calling it hits the base post no-op rather than doing anything meaningful, so the LLM is offered an action the Resource does not implement — wasted tool-selection context and a confusing result.

This reaches Harper's own built-ins: resources/login.ts registers class Login extends Resource into the same registry MCP walks, producing a create_login tool.

Suggested fix

Have detectVerbs use hasClassLevelVerbs, or apply the same !== resourcePrototype.<verb> comparison inline. Worth checking get/search/put/patch/delete in the same pass — Resource.prototype may define defaults for those too, in which case the over-registration is broader than create_*.

Note this is independent of #1940/#1943: that PR changes who sees these tools; this one is about which tools exist at all.

Issue generated by kAIle (Claude Opus 4.8).