stop_activity

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

No annotations are provided, so the description must cover behavioral traits. It discloses the ability to backdate with at or stopped_minutes_ago and the condition for type_name, which is useful. However, it does not mention what happens if no activity is active, whether the interval is definitively closed, or any side effects, leaving the agent without full awareness of edge cases.

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 two sentences long, front-loaded with the core purpose, and every sentence adds important operational detail. There is no filler or repetition of schema content, making it appropriately concise and well-structured.

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 five parameters and no output schema, the description covers the main purpose and adds key usage semantics. It is fairly complete for a simple stop tool, though it could briefly note error conditions (e.g., no active activity) or what is returned. The schema handles parameter details, so this slight gap does not significantly impair context.

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 coverage is 100%, so the baseline is 3. The description adds semantic value beyond the schema by explaining that type_name may be omitted when exactly one activity is active and by clarifying that at and stopped_minutes_ago are alternative backdating options. This helps the agent understand parameter relationships and selection.

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 tool stops a running or paused activity, using a specific verb and resource. It distinguishes from siblings like start_activity and pause_resume_activity by indicating it ends an activity. The nuance about omitting type_name when exactly one activity is active also reinforces the purpose.

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 gives clear context for when to use the tool (to stop an activity) and includes a specific condition: type_name may be omitted when exactly one activity is active. However, it does not explicitly compare with alternatives like pause_resume_activity or update_activity, so it stops short of full when/when-not guidance.

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