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

Annotations already declare destructiveHint=true, readOnlyHint=false and openWorldHint=true, so the safety profile is covered structurally. The description adds that completion "closes" the task, but says nothing about reversibility/undo, whether recurring tasks advance, or the fact that the `confirm` parameter is a no-op.

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 effect, followed by the one operational hint an agent needs. No filler.

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 rich annotations, the description covers what the tool does, the required input, and its source. It could say more about irreversibility or the vestigial `confirm` flag, but nothing essential for correct invocation is missing.

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%, including the note that `confirm` is ignored, so the schema carries the parameter burden. The description only adds the provenance hint that task_id comes from todoist_list_tasks, which is helpful but minimal.

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 ("Mark a Todoist task complete") and clarifies the effect with "(closes it)". The Todoist qualifier distinguishes it from the many sibling completion tools (complete_reminder, complete_omnifocus_task, todo_complete_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?

The description supplies a useful workflow prerequisite: obtain the task_id from todoist_list_tasks. However, it gives no explicit when-not guidance or cross-reference to the sibling task-manager completion tools, so the agent must infer which completion tool suits which backend.

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