Mark Todo Done

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

Annotations already indicate that the tool is idempotent and not destructive. The description adds no behavioral details beyond the action itself, which is acceptable given the annotations cover safety aspects.

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 sentences, front-loaded with the action, and no extraneous content. Every sentence is essential and efficiently conveys purpose and requirement.

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?

Given the simplicity of the tool (mark a todo done), the presence of annotations, and full schema coverage, the description sufficiently covers what the agent needs to know. No output schema is needed for this action.

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%; both 'todoId' and 'userCredentials' are well described in the schema. The description reinforces the ID format but does not add novel meaning beyond the schema.

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?

The description clearly states the action ('Mark a single to-do item as done') and the resource (todo item for authenticated user). The name and title align, and it implicitly distinguishes from sibling tools like 'mark_all_todos_done' and 'restore_todo'.

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 explains that the todo ID must come from 'list_my_todos' and specifies acceptable formats. It does not explicitly list when not to use this tool or mention alternatives like 'mark_all_todos_done', but the sibling context and name provide enough guidance.

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