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

Annotations already mark the tool as readOnly, and the description adds useful context that it requires no authentication and is free. It also clarifies what content the card contains, but does not describe response structure or any other behavioral details beyond the read-only safety profile.

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 concise sentence that front-loads the core subject and immediately communicates the important access characteristics. Every word earns its place.

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 parameterless, read-only metadata tool, the description covers purpose, contents, and access requirements. It is reasonably complete even without an output schema, though it could explicitly mention that the tool returns the card contents.

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 parameter documentation is not needed. The baseline of 4 applies because there is no schema information requiring compensation.

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 identifies the tool's purpose: returning the A2A agent card with identity, skills, endpoints, and write-authentication details. It is specific enough to distinguish from action-oriented siblings like submit_wish or endorse_wish, though it does not explicitly name them.

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 implies this tool should be used when you need to learn about the agent's capabilities and access requirements. It states 'Free, no auth' as access context, but gives no explicit guidance about when to prefer this over sibling tools such as list_services or get_signing_instructions.

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