Update a time entry

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

Annotations already declare a non-destructive, idempotent mutation, and the description adds meaningful partial-update semantics ('only the fields passed change'). It does not disclose permission requirements, error behavior, or what happens to omitted fields beyond the partial-update implication.

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?

A single front-loaded sentence with no wasted words, and the partial-update qualifier earns its place. It is efficient, though its terseness contributes to the gaps scored elsewhere.

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 five-parameter mutation tool with low schema description coverage and no output schema, the description is too thin. It omits parameter semantics for four fields and any usage context, leaving the agent under-informed despite the safety annotations.

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 only 20% (id is documented; hours, comments, spent_on, activity_id are not). The description does not compensate by explaining any of those four parameters, so an agent gets no added meaning for most inputs.

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 specific verb and resource ('Updates a time entry'), which cleanly distinguishes it from sibling time_log (create) and time_delete_entry (delete). However, it does not explicitly name or differentiate from those siblings, so it stops short of a 5.

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?

Provides no guidance on when to use this tool versus time_log or time_delete_entry, nor any prerequisites or exclusions. The only usage-adjacent statement is the partial-update note, which is behavioral rather than contextual.

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