complete_todo

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. While 'Mark a todo as completed' implies a mutation (state change), it lacks details on permissions required, whether the operation is idempotent (e.g., what happens if the todo is already completed), side effects (e.g., updates to completion timestamps), or error conditions. For a mutation tool with zero annotation coverage, this is a significant gap in transparency.

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, efficient sentence with zero waste—'Mark a todo as completed' directly conveys the core functionality without extraneous details. It is front-loaded and appropriately sized for a simple tool, making it easy for an agent to parse and understand quickly.

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 that this is a mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain what 'completed' entails (e.g., status field update, timestamp), potential side effects, error handling, or return values. For a tool that modifies data, more context is needed to ensure safe and correct usage by an agent.

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 input schema has 100% description coverage, with the single parameter 'todoId' clearly documented as 'Todo ID to complete'. The description adds no additional parameter information beyond this, but since schema coverage is high and there's only one parameter, the baseline score is elevated. The description implicitly reinforces that a todoId is needed to perform the completion action.

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') and resource ('a todo') with the specific state change ('as completed'), making the purpose immediately understandable. It distinguishes this from sibling tools like 'toggle_todo' and 'uncomplete_todo' by specifying completion rather than toggling or reversal. However, it doesn't explicitly mention what 'completed' means in this context (e.g., status change, timestamp update).

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 provides no guidance on when to use this tool versus alternatives like 'toggle_todo' or 'uncomplete_todo', nor does it mention prerequisites (e.g., the todo must exist and be pending). It simply states what the tool does without contextual usage instructions, leaving the agent to infer appropriate scenarios from the tool name alone.

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