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

Annotations already declare readOnly/idempotent/closed-world, so the description's added value is the index-only, no-fabrication guarantee, the note that provenance metadata rides on the response, and the warning that org narrative fields are untrusted per ADR 0008. That is meaningful context beyond the annotations, though it stops short of saying what happens for a missing/invalid id.

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 action and the sibling routing before the caveats, and every clause carries information. The back half is dense with internal jargon ('Wave BI provenance', 'ADR 0008') that could be opaque without project context.

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 still covers source, trust model, and provenance, which is largely sufficient for a thin single-row lookup. It does not indicate what fields a claim row contains or how a not-found id is signalled, a minor 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 coverage is 100% and the single parameter already carries a pattern, an example, and the claim_id description. The description repeats the example id but adds no new meaning about the parameter, so the baseline 3 applies.

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 and resource (fetch one claim row by claim_id) plus the backing source (data/claims_index.json). The example id makes the identifier shape concrete, and naming list_claims as the browsing counterpart separates it from the sibling tool without needing schema inspection.

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?

Explicitly routes the agent: use this when you have a single claim_id, use list_claims with filters when browsing. That is a named alternative plus the condition that selects it, which is the top of the scale for a one-parameter getter.

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