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

Annotations already declare readOnly/openWorld/non-destructive, so the safety profile is covered. The description adds the crucial behavioral fact that results are capped at the 10 newest notices and lists exactly what fields come back, which is the main thing an agent needs to know before deciding whether this tool suffices.

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 first sentence is front-loaded and efficient, but the second is an overlong run-on that mixes the return summary with promotional cross-references to a paid Apify Actor and a list of unrelated portals. That marketing tail dilutes the signal an agent needs.

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 four-parameter search tool with no output schema, the description covers the data source, result cap, and returned fields, which is enough to invoke correctly. Only the recency window and any rate-limit or auth expectations are left to the schema or omitted.

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%, so the schema already defines days, keywords, countries and the type enum. The description restates the type mapping (open tenders / planned procurements / contract awards) and the ISO-code country scope but adds no format or edge-case detail beyond the schema; the days window is not mentioned at all. Baseline 3 is appropriate.

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?

"Find recent public procurement notices of the EU's official TED portal" is a specific verb plus resource with scope (27 EU countries + EEA) and the three searchable record types named inline. An agent can distinguish this from every sibling tool, none of which touch procurement data.

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 names the search axes (keywords, buyer country, type) and explicitly routes the agent elsewhere for more than 10 notices, other portals (UK Find a Tender, Contracts Finder, SAM.gov, Grants.gov), CPV/NAICS filters or alerts. It stops short of stating when this tool is the wrong choice beyond that single escalation hint, so a 4 rather than a 5.

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