List documents

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

Adds significant behavioral detail beyond readOnlyHint annotation: explains the 'cancelled' vs 'declined' mapping and the required reporting behavior. No contradiction with annotations.

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 front-loaded sentences with no redundancy. Each sentence adds distinct value: purpose, behavioral nuance, and pagination guidance.

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?

Covers main functionality: listing, filtering, pagination, and crucial status interpretation. Could mention return fields but is sufficient given no output schema and simple param list.

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?

Adds meaning to limit/offset (pagination) and explains the status filter's virtual 'declined' mapping. Schema has 33% coverage; description compensates for the undocumented params.

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?

Clearly states verb 'List', resource 'sender's documents', and ordering 'newest first'. Differentiates from siblings like list_templates and other action-oriented tools.

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?

Provides context on filtering by status and pagination, and an important instruction on reporting cancelled status as declined. Could be more explicit about when to use this vs siblings, but the context signals help.

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