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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower. The description adds genuine behavioral context beyond them: result ordering (newest position date first), the per-row payload including source credit, and the market-availability caveat.

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?

Front-loaded with purpose and scope in a single dense sentence, with no filler. Listing every returned column is somewhat redundant given an output schema exists, but overall it is efficient.

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 paginated, fully-annotated read tool with a complete schema and an output schema, the description covers scope, filtering, ordering, and market availability. Only minor behavioral details like pagination semantics remain, and those are already in the schema.

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 baseline would be 3, but the description adds meaning by clarifying market liveness and that the UK is not offered even though 'uk' appears as a schema value for country. The issuer-id filter is largely redundant with the schema, keeping it from a 5.

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 and resource (European disclosed net short positions) and enumerates the exact fields returned, which distinguishes it from the other EU tools (insider dealings, major holdings, annual reports). The market scope (Sweden/Netherlands/Denmark, not UK) further sharpens what this tool is.

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?

Gives clear operational context: filter by issuer id and check get_eu_markets for which markets are live, plus the explicit 'not offered for the UK' exclusion. It stops short of naming a sibling alternative to use instead, so it is strong guidance but not a full when/when-not/alternative statement.

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