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

Beyond the annotations (readOnly, idempotent, non-destructive), the description adds meaningful behavioral context: results are deterministic and validated, the index layer is always free, and content layers require a trial key on the ethics vertical. This adds value without contradicting the annotations.

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 (three sentences) and front-loaded with the core purpose. Each sentence adds distinct information: what it does, what it returns, and access/cost details. No unnecessary repetition.

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 retrieval tool with no output schema, the description gives a reasonable overview but lacks detail on the structure of the returned knowledge nodes and the exact meaning of 'content layers' and 'index layer'. The enum of verticals is in the schema, but the description could better bridge the access model and expected results.

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 already provides 100% description coverage for all three parameters, so the description does not need to re-explain them. However, the description's mention of 'index layer' and 'content layers' only loosely relates to the token and vertical parameters, and it does not clarify parameter-specific usage 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 the tool's action ('Retrieve structured knowledge') and resource ('Agent Module verticals'), and mentions the output type ('deterministic, validated knowledge nodes'). This distinguishes it from sibling tools like check_status or get_trial_key, which serve different purposes.

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 describing what can be retrieved and the access conditions (index free, trial key on ethics), but it does not explicitly state when to use this tool versus alternatives, or provide any exclusions or prerequisites beyond the access note.

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