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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is clear. The description adds significant behavioral detail: it uses the official ClinicalTrials.gov API v2, is free with no login needed, costs $0.02/call, and provides real-time updates with sorting by most recent. This fully leverages the provided context.

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 sentence with precise details: what is watched, output fields, sorting, data source, pricing, and authentication. Every word adds value with no redundancy. Front-loaded with the core purpose.

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 has 4 parameters with 100% schema coverage, readOnlyHint and openWorldHint annotations, and no output schema, the description is complete. It clarifies the output format (NCT id, status, phase, sponsor, URL), data source, cost, and free access model. No missing information for an agent to select or invoke this tool correctly.

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 coverage is 100%, so each parameter is already described in the schema. The description adds context that the queries are for 'conditions, drugs or sponsors' and that the tool returns 'one or more matching trial rows per query', which clarifies the array nature of results beyond schema details. However, it does not explain the behavior of 'maxConcurrency' 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 monitors new and updated clinical trials for specified conditions, drugs, or sponsors, and lists the output fields (NCT id, status, phase, sponsor, study URL). This is specific and distinct from sibling tools like 'fda-approval-feed' or 'drug-adverse-events', which focus on approvals or adverse events.

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 explains monitoring of clinical trials with explicit output fields and sorting, but does not mention when to use it versus alternatives like 'fda-approval-feed' (which covers approvals) or 'sec-edgar-watcher' (financial filings). It implies use for clinical trial tracking without excluding other contexts.

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