register_agent

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

With no annotations provided, the description carries the full burden. It discloses that the tool performs a write operation ('stores it in the server's list') and involves fetching from a URL, indicating network activity. However, it doesn't mention potential errors (beyond a vague reference), authentication needs, rate limits, or idempotency. The description adds some behavioral context but leaves gaps for a mutation tool.

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 well-structured with a clear opening sentence, followed by explanatory details and separate sections for Args and Returns. It's appropriately sized for a tool with one parameter and no output schema, though the Returns section could be more concise. Every sentence adds value, with no redundant information.

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 complexity (a mutation with network operations), no annotations, 0% schema coverage, and no output schema, the description is moderately complete. It covers the purpose, parameter meaning, and return value structure, but lacks details on error handling, side effects, or interaction with siblings. For a registration tool in an A2A system, more behavioral context would be beneficial.

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 input schema has 0% description coverage (no titles or descriptions for parameters), so the description must compensate. It provides clear semantics for the single parameter 'url', explaining it's 'the base URL of the A2A agent to register' and should point to where the agent's card can be resolved. This adds meaningful context beyond the schema's bare type, though it doesn't cover format examples or validation rules.

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 the tool's purpose: 'Registers an Agent-to-Agent (A2A) agent with the bridge server' and explains it fetches and stores agent information. It distinguishes from siblings like 'list_agents' (which likely lists registered agents) and 'unregister_agent' (which removes them), though it doesn't explicitly contrast them. The verb 'registers' is specific and the resource 'agent' is well-defined.

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 usage by mentioning that it makes the agent 'available for communication,' suggesting it's for setting up A2A interactions. However, it doesn't explicitly state when to use this tool versus alternatives like 'send_message' (which might require a registered agent) or 'unregister_agent,' nor does it mention prerequisites or exclusions. The guidance is contextual but lacks explicit alternatives.

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