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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. Beyond that the description adds nothing: no mention of what a mandate record contains, what happens when the id is unknown, or whether the apiKey alternative matters on this door.

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 short sentences, front-loaded with the action and followed by the prerequisite; there is no filler. The economy is partly under-specification rather than pure efficiency, but nothing extraneous is present.

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 getter with a two-parameter schema and no output schema, the description is minimally sufficient to call it. It leaves the agent without any sense of the returned shape or error behavior, which a short second sentence could have fixed.

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 50%: apiKey is documented in the schema, mandateId is a bare string. The description's "Needs mandateId" only restates the required flag the schema already enforces, and says nothing about the id's format or provenance, so it does not compensate for the coverage gap.

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?

"Read one mandate" gives a specific verb plus resource, and the singular "one" implicitly distinguishes it from the sibling list_mandates. It stops short of naming that sibling or saying what a mandate is, so an agent must infer the distinction from the name alone.

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?

"Needs mandateId" signals the prerequisite for calling it, and the singular framing implies it is the single-record counterpart to list_mandates. However, no explicit when-to-use or when-not-to-use guidance is given, and no alternative is named.

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