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

Annotations supply only destructiveHint=true, so the description adds meaningful behavioral context: the underlying REST call (PATCH /time_entries/{id}/stop), the fact that it is a write, and the non-idempotent error behavior when the entry is already stopped. It stops short of covering return payload, side effects on the timer, or auth requirements.

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?

Three short, front-loaded fragments with no filler. The trailing 'WRITE — modifies data' partially duplicates the destructiveHint annotation, but the overall density is good.

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 single-parameter mutation with no output schema, the description covers what the tool does, the state requirement, the error edge case, and the endpoint. Nothing an agent needs in order to call it correctly is missing.

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% and the single parameter is fully documented in the schema, so the baseline is 3. The description adds only the implicit constraint that the id must reference a *running* entry, which is a marginal gain over the schema's 'running time entry id to stop'.

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?

States a precise verb and resource ('Stop a currently running time entry'), which is unmistakably distinct from siblings like harvest_restart_time_entry, harvest_delete_time_entry, and harvest_update_time_entry. An agent can identify the operation without opening the schema.

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 parenthetical clarifies the state in which the call is valid ('currently running') and that an already-stopped entry produces a no-op error, which implies usage context. However, it never explicitly routes between this tool and its closest sibling, harvest_restart_time_entry, nor states prerequisites such as needing the entry to belong to the current user.

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