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

Annotations already declare readOnlyHint=true, idempotentHint=true and openWorldHint=false, so the safety profile is covered. The description adds value by disclosing the record's payload contents, but says nothing about auth, rate limits, or whether a missing id/country errors versus returns empty. Adequate but not rich beyond the 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?

A single front-loaded noun phrase that lists the returned fields without padding; every word earns its place. It is slightly terse as a fragment with no verb, but nothing is wasted.

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?

There is no output schema, so the description usefully compensates by enumerating the record's contents. For a read-only, two-parameter lookup whose safety profile is fully carried by annotations, this is nearly complete; the only gap is how it relates to assay_supplier_contracts and other supplier-oriented siblings.

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%: both id and country are fully documented in the schema, including the 'id as given by assay_search' provenance and the country-code format. The description adds no parameter-level meaning, 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?

It states a specific resource and scope ('One supplier's record') and enumerates the record contents (contracts won, buyers, totals, exclusions, grants, source, licence), which tells an agent exactly what it gets back. It does not distinguish itself from close siblings such as assay_supplier_contracts or assay_contract, so the agent must infer the boundary.

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 gives no when-to-use guidance, no prerequisites, and names no alternative. The only routing hint ('the part after the country in the endpoint') lives in the schema, not the description, and no sibling is contrasted.

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