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

Annotations only declare destructiveHint=true, so the description carries the behavioral load and does so well: it discloses patch semantics ('Only the fields given are changed') and the destructive replace-list behavior of 'users replaces the whole list'. It omits auth/permission needs and side effects of moving between lists or workflows.

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 the verb and full capability list, followed by one critical semantic caveat and an endpoint reference. No filler sentences; every clause carries information.

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 10-parameter mutation tool with no output schema and only a destructiveHint annotation, the description covers the key semantics (partial update, list replacement, endpoint). It could still mention permissions or failure behavior, but an agent has enough to call it correctly.

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 the schema already documents each parameter, including that users is the 'New FULL list of assignee user ids'. The description's 'users replaces the whole list' largely restates that, adding little beyond the schema, so the baseline 3 applies.

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 (update) plus resource (task) and enumerates every updatable facet (name, description, assignees, due date, priority, completion, list, status). It is easily distinguished from paymo_create_task and paymo_get_task.

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 implied by the field enumeration, and 'Only the fields given are changed' communicates partial-update behavior, but there is no explicit when-to-use vs alternatives guidance or prerequisite/permission note, and no sibling is named.

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