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

Annotations supply only destructiveHint=true, so the description must carry the rest, and it does add real context: the partial-update guarantee ('Only the fields given are changed') and the overwrite semantics of 'users replaces the whole list', which is exactly the kind of destructive behavior an agent needs warned about. It stops short of permissions, error handling, or what happens to omitted vs. empty values.

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 action and its full field list, followed by one short behavioral caveat and the endpoint reference. Dense but every clause maps to a real capability; the 'Paymo: PUT /api/tasks/{id}' tail is marginal but cheap.

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, the description covers the mutation semantics, the overwrite hazard on assignees, and the endpoint, which is what an agent needs to call it safely. Missing are failure modes (invalid task_id/status_id) and whether changes are reversible, which the destructiveHint alone does not clarify.

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 100%, so every parameter is already documented, and the description's field mapping (complete/incomplete, tasklist_id/workflow status) largely restates it. The 'users replaces the whole list' note duplicates the schema's own 'New FULL list of assignee user ids' text, adding no new syntax or format detail. Baseline 3 applies when the schema does the heavy lifting.

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?

Names a specific verb (update) and resource (task), then enumerates the exact mutation surface: rename, re-describe, reassign, due date, priority, complete/incomplete, move task list or workflow status. This clearly separates it from siblings like paymo_create_task, paymo_get_task and paymo_update_time_entry.

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 enumeration of editable fields, and 'Only the fields given are changed' signals the partial-update contract. However, it never states when to prefer this over alternatives (e.g. create vs update, or how it relates to paymo_update_time_entry), nor any preconditions such as the task needing to exist.

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