Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already establish readOnly/idempotent/no-destructive, so safety is covered. The description adds real behavioral context beyond that: it 'reports what the index holds and adds no verdict of its own,' and it is limited to HTTP operations that a consumer call wins onto — both meaningful scope disclosures. It stops short of describing pagination mechanics, though the schema covers those.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core action and its outputs, then usage triggers, then routing alternatives, then a reference URL. Dense but each sentence does work; the parenthetical enumeration of returned fields is slightly listy but earns its place given there is no output schema.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, an 8-parameter surface, and reach into sibling routing, the description compensates well: it enumerates what is returned (producer request/response types, consumer call sites with expected types, stored verdict plus scanner version) and maps the tool against its nearest siblings. Nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% (path, repo, limit, offset, project, method, service fields all documented, including the dispatch-suffix nuance), so the schema carries the parameter burden. The description adds no syntax or format detail beyond it, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Specific verb ('put side by side, operation by operation') plus resource (consumer/producer pair) plus scope (HTTP operations, stored type verdicts with scanner version). It explicitly distinguishes itself from get_endpoint_types ('producer's types alone') and check_compatibility ('which calls match at all'), so an agent can route without inspecting schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives two concrete triggering situations ('about to change a shape', 'a compatibility verdict names a problem you cannot place') and explicit exclusions: GraphQL/socket/pub-sub pairs go to check_compatibility, producer-only types go to get_endpoint_types, matching goes to check_compatibility. When/when-not/alternatives are all covered.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.