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

Annotations declare readOnlyHint=true, and the description aligns with that. It adds meaningful context: quarterly update cadence, historical data since 1995, data source (Eurostat EDP), and output composition (confidence, top_drivers, source_lineage). It does not detail edge cases or limitations, but the read-only nature is clear.

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?

Three sentences deliver a dense but structured description: output formula/content, usage triggers, and update frequency. No wasted words, though the first sentence is a bit long. The structure is clear and front-loaded with the core purpose.

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 single-optional-parameter read-only tool with no output schema, the description is complete. It covers what the tool returns, the data source, the time frame, update cadence, and specific use cases. The agent can confidently select and invoke this tool without missing critical context.

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%, with the sole 'days' parameter fully documented in the schema. The description adds little beyond what the schema already states, only reinforcing the optional historical series concept. Baseline of 3 is appropriate because the schema carries the semantic weight.

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 uses a specific action ('Returns') and names the exact resource and scope ('Euro-Area fiscal sustainability gap score'). It also includes the calculation formula and output fields, making it immediately distinguishable from other adw tools despite the opaque sibling names.

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?

Explicit call-use conditions are provided ('Call when the user asks about eurozone sovereign debt, government deficits, Maastricht compliance, or EU fiscal health') plus a financial use case ('timing credit-spread assumptions'). It does not mention alternative tools or when not to use it, holding it back from a 5.

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