Machine-readable contract

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

The readOnlyHint annotation already covers the safety profile; the description adds that the contract is 'live' (current), that credentials are required, and it specifies the coverage areas. This goes 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?

One dense sentence with no filler: the primary purpose is front-loaded, the content categories are enumerated, and the credential requirement is a single trailing clause.

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?

For a zero-parameter, read-only contract endpoint, the description lists the major content areas and flags authentication. It does not state the response format, but the title 'Machine-readable contract' partially covers that, and no output schema exists to fill the gap.

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?

There are no input parameters (schema has zero properties, coverage 100%), so the baseline is 4. The description cannot add parameter meaning, but its content list indirectly informs what will be returned rather than what to pass.

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 identifies the tool's resource ('the live API contract') and enumerates the categories it covers, so an agent can tell it apart from sibling tools like guide or whoami. It lacks an explicit retrieval verb (e.g., 'get'), but 'contract' plus the content list 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?

No guidance about when to call this tool versus any of the eighteen siblings; the only usage hint is the requirement for credentials. An agent must infer that this is the place to learn API limits before using other tools.

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