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

Annotations already signal readOnlyHint=false and destructiveHint=false, so the description's 'Create' is consistent. The description adds helpful context beyond the annotations by explaining the priority scale (1=normal to 4=urgent) and giving examples of natural-language due strings, which aids in correct usage. It doesn't disclose potential side effects, but for a simple create operation, this is sufficient.

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?

The description is a single, front-loaded sentence that states the core action first and then lists optional parameters efficiently. It contains no filler or redundant information, making it easy to parse and act upon.

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 simple creation tool with an output schema available, the description covers the essential purpose and key options. It doesn't explain return values, but that's unnecessary given the output schema. It could theoretically mention prerequisites like needing a connection, but the sibling connect_todoist implies that; overall, it's complete enough for an agent to invoke 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 description coverage is 100%, so the baseline is 3. The description essentially restates the schema's parameter descriptions: it mentions project, due_string with examples, and priority with the same scale. It adds no new meaning beyond what the schema already provides, so it doesn't exceed the baseline.

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 explicitly states 'Create a Todoist task' with a clear verb and resource, and distinguishes itself from siblings like todoist_complete_task and todoist_list_tasks by focusing on creation. It also briefly lists key optional parameters, leaving no ambiguity about what the tool does.

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 clearly implies use when creating a new task in Todoist, providing examples for due dates and priority levels. While it doesn't explicitly mention alternatives, the specificity of 'Create a Todoist task' and the optional parameters give clear context. No exclusions are stated, but the purpose is unambiguous enough for an agent to select it appropriately.

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