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

No annotations are provided, and the description does not disclose behavior beyond the name. It doesn't explain return format, potential errors, or whether it performs network calls. Since annotations are absent, the description carries full burden but only offers a minimal phrase.

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 extremely short, which is concise, but it lacks structure. It's just a single phrase without any additional context. While not verbose, it's not effectively organized to aid understanding.

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?

The description is inadequate for a tool with no annotations, no param descriptions, and an unknown output schema. It doesn't provide enough context about what the tool does, what input to provide, or what to expect in return, making it insufficient for reliable invocation.

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 only parameter 'q' has zero schema description, and the tool description adds no meaning. The agent cannot infer what format the query should take (e.g., an email, a URI). With 0% schema coverage, the description fails to compensate.

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 it performs 'WebFinger resource discovery' and mentions ActivityPub/OIDC, giving a clear purpose. However, it doesn't explicitly differentiate from siblings like 'wellknown' or other discovery tools, leaving ambiguity about when this specific tool is needed.

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. The description doesn't mention any context, prerequisites, or exclusions, so an agent has no clue about selection criteria.

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