Describe an endpoint

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

The readOnlyHint annotation already establishes the tool is non-destructive. The description adds output-related context such as 'danger level' and 'security alternatives', but it does not address tool-specific behaviors like rate limits or auth requirements. This adds some value beyond the annotation without contradicting it.

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?

The description is a single, compact sentence that is front-loaded with the main purpose. It lists the output aspects without wasted words. It could mention the input format for the endpoint, but the schema covers that, keeping the text appropriately lean.

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 only 3 parameters, all fully described in the schema, and a read-only annotation, the description covers the tool's purpose and output scope reasonably well. The output schema is absent, so the description's enumeration of response aspects is helpful. It lacks explicit alternatives but is otherwise complete enough for straightforward invocation.

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%, with each parameter (endpoint, mode, depth) already documented including enums and defaults. The description's mention of 'compact, depth-limited' hints at the effect of depth/mode, but it does not add significant new meaning beyond the schema baseline.

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?

The description states a specific resource ('one endpoint') and the details it provides: parameters, request/response shapes, danger level, security alternatives, and URL. While it does not explicitly differentiate this tool from siblings like api_schema or api_get, the 'one endpoint' scoping and the list of output aspects make the purpose clear.

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 description gives no guidance about when to use this tool versus the alternatives. It does not mention search, spec-level information, or other tools, and there are no usage prerequisites or exclusions. An agent must infer from the sibling names, which is insufficient.

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