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

Annotations already cover the safety profile (readOnly, non-destructive, openWorld), yet the description adds genuinely new behavioral facts: results are scored candidates and `pep` flips true only above a 0.7 match threshold. That threshold is the key decision rule for interpreting output and is not available anywhere in the structured fields. It stops short of noting hit/miss ambiguity or candidate volume.

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 compact sentences, front-loaded with the dataset and output shape, then parameter hints. Every clause carries information the caller needs and nothing is repeated from annotations or schema.

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?

With an output schema present and annotations covering read-only/open-world semantics, the remaining burden is interpretation of results and inputs, both of which the description handles via the 0.7 threshold rule and parameter formats. The only gap is guidance on how to act when the score is near but below the threshold, or which sibling to escalate to.

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 0%, so the description must carry the burden, and it does: `birth_date` is given a concrete format (YYYY-MM-DD, partial accepted) and `country` accepts either a name or ISO code. Both optional parameters gain actionable syntax that the schema lacks; only `name` is left unstated, which is acceptable given its obviousness as the sole required field.

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 ("Screen a person's name against the OpenSanctions PEP dataset") and names the exact external data source, which immediately separates it from siblings like screen_email, screen_country, and screen_crypto_address that screen other resource types. An agent can route to it without opening the 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?

Usage is only implied by the resource type; there is no explicit statement of when to prefer this over a sibling or what to do when a person may be a PEP under a different name spelling. It never names an alternative tool or an exclusion condition, so the agent must infer routing from the tool name alone.

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