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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds no further behavioral context (e.g., pagination, output format, or size limits). Since the annotations carry the burden, a 3 is appropriate—the description doesn't contradict or extend beyond what annotations provide.

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, efficient sentence that immediately states the action and provides a practical hint. There is no fluff or redundant information. It earns a top score for conciseness.

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?

Given the tool's simplicity (no params, no output schema) and that annotations cover safety, the description is fairly complete. It tells the agent what the tool returns (available specs) and how to use that result (select by title). It doesn't specify the exact output structure, but for a listing tool, this is likely sufficient for an agent to proceed. A 4 is reasonable.

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?

The tool has zero parameters, so the schema trivially covers all parameters (100% coverage). The baseline for 0 params is 4. The description's note about using the title to select a spec applies to the output, not parameters, so it doesn't add param-specific meaning, but no param semantics are needed. A 4 is fair.

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 clear verb ('Lists') and resource ('all available OpenAPI specs'), and the title reinforces it. It distinguishes itself from siblings like list-endpoints and search-endpoints by specifying 'specs' rather than endpoints, though it doesn't explicitly contrast them. Still, the purpose is unambiguous.

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 on when to use this tool versus alternatives. It only hints at a follow-up action ('Use the title to select a spec') but does not mention any other tools or exclusions. An agent would have to infer usage from the name and siblings, which is insufficient.

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