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

With no annotations, the description must carry the burden of disclosure. It mentions the response format (agent cards, A2A-compatible) and a 200 response with content-type, but does not state read-only semantics, pagination behavior, error handling, or any side effects. The absence of a readOnlyHint makes this a notable gap.

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 concise and front-loaded with the title and key purpose. The 'Responses' section is minimal but not overly verbose. It avoids unnecessary fluff, though it could be better structured with more meaningful response details.

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 4 optional parameters, no output schema, and no annotations, the description is incomplete. It does not explain how to use pagination (top, cursor) or filtering (q, category), nor does it describe the agent card structure or any error conditions, leaving a substantial gap for an agent to correctly invoke the tool.

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 75% (q, cursor, category are described, top is not). The description adds no parameter-level meaning, failing to compensate for the undocumented 'top' parameter or explain how q, category, and cursor interact. It adds no value beyond the schema.

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 clearly states it returns agent cards in an A2A-compatible format, using the verb 'returns' with a specific resource. It does not explicitly differentiate from sibling tools like list_agents or search_agents, but the A2A compatibility and 'open discovery endpoint' provide some distinguishing context.

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 is provided on when to use this tool versus alternatives. It does not mention any exclusions, prerequisites, or comparison to sibling tools such as discover_single_agent or list_agents, leaving the agent without decision support.

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