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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety bar is low. The description adds real behavioral context beyond them: result ordering (newest first), the exact fields returned, CC BY 4.0 licensing, and an explicit cost of 1 point per returned record.

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?

Two tight sentences, front-loaded with the core verb+resource, then filters and cost. No filler or redundancy; every clause contributes information.

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?

All 8 parameters are documented in the schema, there is no output schema, and the description compensates by listing returned fields, pagination-free result ordering and cost. Only the absence of guidance about alternative funding sources keeps it short of a 5.

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 description coverage is 100% and both enum parameters are fully documented in the schema, so the schema carries the load. The description only repeats the filter categories (country, stage, sector, minimum amount, dates) without adding format or syntax meaning, so 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 (Search) and resource (European startup funding rounds) with source attribution (Tech.eu Funding Explorer) and names the returned fields. An agent can distinguish it from siblings like run_techeu_exits_search or run_techeu_companies without opening a schema.

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?

It implies usage via the filter list and the 'newest first' ordering, and mentions cost ('1 point per returned record'), but never states when to choose this over competing funding sources (crunchbase, pitchbook, dealroom, tracxn siblings) or any exclusions/limitations.

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