describe_endpoint

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description still adds real behavioral context the annotations cannot: that the result carries the full transitive schema closure rather than a shallow operation record, which is the key trait an agent needs to trust it for request-body construction. It omits error/not-found behavior for an unresolvable operation_id.

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?

Two sentences, zero filler, and the payload guarantee is front-loaded right after the purpose. Nothing repeats the name or the annotations.

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?

An output schema exists, so return structure need not be restated, and the description covers purpose, scope and the semantic completeness of the result. The remaining gap is routing guidance against list_endpoints and any failure mode for ambiguous or unknown operation_ids.

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%: the schema already explains the qualified vs bare operation_id form and the api fallback for disambiguation. The description adds nothing about either parameter, 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?

"Describe one OpenAPI operation" states a specific verb and a tightly scoped resource, and the second sentence pins down exactly what the response includes (the operation plus every transitively reachable components.schemas entry). An agent can distinguish this from list_endpoints (enumerate many) and call_endpoint (invoke) without opening any schema.

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?

The phrase "so a request body can be built without the full spec" implies the workflow position (inspect before composing/calling), but the description never explicitly says when to use this versus list_endpoints or call_endpoint, nor when not to use it. Usage is inferable rather than stated.

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