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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and non-destructive behavior. The description adds useful context beyond this: it characterizes the data as human-reviewed, includes 'Phase 1 ORR flag-only data', provenance, extractor versions, and pending-review counts, and clarifies the relationship to engine 2.6.0. No contradiction with 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?

Two sentences, front-loaded with the primary purpose and data contents, followed by a concise usage directive. Every sentence adds value; no filler or redundancy.

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 tool has a single parameter and an output schema, so much of the return structure is externally documented. The description covers the tool's role, data composition, and nuance about 'Phase 1 ORR flag-only data'. It lacks explicit details on pagination or authorization, but these are not critical given the schema and read-only annotations.

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 description coverage is 100%, with a clear description for project_id. The tool description adds no additional parameter-level semantics beyond what the schema already provides, so the baseline of 3 is appropriate.

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 opens with a specific verb ('Fetch') and clearly identifies the resource ('human-reviewed drug-specific clinical-risk signals for a project'), then enumerates the included data elements. This unambiguously distinguishes it from sibling tools like query_benchmarks or get_evidence.

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 explicitly states when to use the tool: 'Use this before interpreting engine 2.6.0 drug-specific multipliers or flags.' This provides clear context, though it doesn't enumerate alternatives or when-not-to-use scenarios.

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