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

The description discloses two non-obvious behavioral traits: cascading to subtasks and handling recurrence. These go beyond the minimal annotations (readOnlyHint=false, destructiveHint=false) and are important because the toggle can affect multiple records, not just the one identified by task_id.

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 one tight sentence that front-loads the core action and appends the two key behavioral caveats. Every word contributes meaning; there is no filler or redundancy.

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 one-parameter toggle with no output schema, the description adequately covers the operation and the main side effects (subtask cascade and recurrence). It leaves slight ambiguity about whether cascading occurs in both toggle directions, but the essential calling context is present.

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?

The only parameter, task_id, is fully described in the input schema as 'ID of the task to complete/uncomplete', achieving 100% schema coverage. The description's toggle language adds a bit of context but no additional parameter detail beyond what the schema already provides, so the baseline of 3 is appropriate.

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 uses a specific verb ('Toggle') and resource ('task') with an explicit state transition ('between completed and pending'), leaving no ambiguity about what the tool does. It clearly distinguishes itself from sibling tools like create_task, update_task, and delete_task by focusing on toggling completion state rather than generic creation, updating, or deletion.

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 implies the intended use: call this tool when you want to toggle a task's completion state. However, it does not explicitly explain when to prefer complete_task over update_task or delete_task, and no exclusions or alternative routing are provided.

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