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

Annotations already cover the safety profile (readOnly, openWorld, idempotent, non-destructive), yet the description still adds genuinely new operational context: ~20 second latency, an eight-source cap, per-user daily search limits, and a PHI warning ('Do not include patient identifiers'). These are traits the annotations cannot express.

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?

Front-loaded with the core capability and result shape, then the routing rules and the safety/limits caveats. Every sentence carries distinct, non-redundant information; nothing is padding.

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 read-only search tool with a declared output schema, the description covers what an agent needs: scope, result count, latency, non-answer behavior, sibling routing, PHI prohibition and rate limits. Return-value structure is already in the output schema, so its absence from the description is not a gap.

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 0% for both parameters, so the schema supplies only names, types and constraints (question minLength 8/maxLength 1000, locale pattern). The description says nothing about what 'question' should contain or what 'locale' affects, leaving the semantics entirely to inference.

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?

Names the specific verb and resource (live search of PubMed, Europe PMC, clinical guidelines) and states scope: up to eight sources with study type, evidence level and link. It explicitly distinguishes itself from ask_cliniatlas (full cited answer) and lookup_eu_medicine (EU label/SmPC), so an agent can route correctly without opening a schema.

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?

Gives explicit when-not guidance: 'It does not write an answer: cite the sources by number, or use ask_cliniatlas' and 'For an EU medicine's label or SmPC, use lookup_eu_medicine.' Alternative tools and the conditions that select them are named directly.

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