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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description goes beyond them by disclosing strict validation behavior ('Every item is required; invalid/missing responses are rejected without defaulting or clamping') and the return shape (total, percent of max, band label + interpretation, citation) despite no output schema.

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?

Dense but front-loaded: instrument specs, then return values, then validation rule, then the educational caveat. The trailing 'Also POST /api/tools/score-instrument' is redundant endpoint trivia that adds little for an agent, a minor structural blemish.

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?

With no output schema, the description supplies the return fields itself, covers both enum instruments with their scoring scales, and states the strict-rejection behavior. For a two-param, nested-object scoring tool this is complete enough to call 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 only 50% (the 'responses' param), but the description compensates with per-instrument semantics: IBS-SSS uses 5 slider items 0-100 plus days×10 (total 0-500) and GERD-Q uses 6 choice items (total 0-18, ≥8 consistent with GERD). It also points to /tools/instruments.json for the item spec, though exact item_ids are left external.

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?

States a specific verb (Score) plus the exact resources (IBS-SSS, GERD-Q) and their scoring ranges, so the agent knows precisely what the tool produces. None of the sibling tools (claim verification, corpus/module reads, relation queries) overlap with clinical instrument scoring, making this easily distinguishable.

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 clear context for use: it scores the two named governed instruments and adds an explicit boundary ('Educational scoring — not a diagnosis'). However, it never states when NOT to use it or names an alternative for, e.g., free-form symptom assessment, so guidance is contextual but not fully routing.

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