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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the important behavioral note that it does not draft an application, which is beyond the annotations. It does not mention pagination or response format, but for a read-only list tool with these annotations, this is acceptable.

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 sentences with zero waste. The purpose is front-loaded, the alternative is given, and the limitation is stated. Perfectly structured for quick agent scanning.

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 simple read-only list tool with optional filters, the description covers the core purpose, the providers, and the key exclusion. It lacks a note on the response format or pagination, but given the low complexity and no output schema, this is a minor gap. The description is sufficient for an agent to decide when to call it.

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%, so each parameter already has a clear description (e.g., emtak 'Matched on the division when the call has rules', provider 'Funder, for example EIS'). The description does not add any additional parameter-level meaning beyond the schema, so the baseline of 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?

The description states a specific resource (funding calls) and the providers (EIS, PRIA, KIK), and explicitly differentiates from the sibling procurement_notices for public tenders. The verb 'Open' is slightly ambiguous but the intent is clear: return open calls. It fully distinguishes this tool from the sibling list.

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 states when not to use it ('Use procurement_notices for public tenders') and adds a limitation ('This tool does not draft an application'). This gives the agent clear routing logic and prevents misuse.

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