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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint false, so safety is covered. The description adds valuable behavioral context beyond annotations: results are newest first, name matching is partial ('Siemens' covers every Siemens entity), and coverage is limited to above-threshold EU procurement. It also describes the return structure (fields and summary), which is not present in annotations or 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?

The description is concise (~4 sentences) and front-loaded with the main purpose. Every sentence adds value: scope, return structure, use cases, name matching caveat, and coverage limitation. There is no fluff or redundancy, and it is well-structured for an agent to quickly grasp the tool's function.

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 query tool with 8 parameters and no output schema, the description is remarkably complete. It explains what the tool does, what it returns (both award list fields and summary metrics), how to use it (use cases, exact name advice), and its limitations (partial matching, above-threshold EU only). The absence of an output schema is compensated by describing the return fields and summary. Minor omissions like pagination behavior are covered by the schema's page/limit parameters.

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?

The input schema has 100% description coverage for all 8 parameters, so the schema already explains each parameter's meaning and format. The description adds a bit of context (e.g., partial name matching, newest-first ordering), but it does not substantially increase parameter understanding beyond what the schema provides. This aligns with the baseline of 3 when schema coverage is high.

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 clearly states a specific verb + resource: 'Award history of one supplier' and details exactly what is returned (contracts won, summary). It distinguishes itself from sibling tools like ted_buyer_profile and ted_search_awards by focusing on a supplier's won awards. The scope is precise: EU public procurement, above-threshold, with partial name matching explained.

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 provides concrete use cases: 'what has Capgemini won', 'who does this supplier sell to', and 'incumbent research before bidding against someone'. It also gives advice on using exact legal names to narrow results. However, it does not explicitly mention alternative tools or when not to use this tool, so it falls short of a full 5.

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