log_time

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

Annotations already declare non-readOnly, non-idempotent, open-world behavior. The description goes beyond them by disclosing the response shape (it repeats the day's new total) and using that to warn about double-logging — a genuinely useful operational cue consistent with idempotentHint=false. It stops short of stating permission requirements or what happens on an ambiguous project/task match.

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?

Four short sentences, front-loaded with the action and followed immediately by the targeting rule, format examples, and the duplicate-detection payoff. Only the closing aside about logging 'the same afternoon twice' is stylistically loose, though it does carry a real warning.

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 six parameters, a fully documented schema, an output schema, and rich annotations, the description supplies the few things structured fields can't: the intent of the operation, the target-resolution rule, and how to read the response. The one omission is any mention of the bulk variant for multi-entry logging.

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%, so every parameter already carries its own documentation, establishing a baseline of 3. The description's duration examples duplicate the schema, and its task-vs-project rule largely restates the schema's 'optional when the project has one task only' note, so added meaning is marginal.

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 states a concrete action and resource: Gryzzly attaches a duration to a task (or a project that resolves to one task). That is enough for an agent to understand this writes a time entry. It never names or contrasts with the obvious sibling log_time_bulk, so differentiation is left to the tool name alone.

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?

It gives a real rule for parameter selection — name a task, or a project whose tasks narrow to one — which implies when the call is valid. However, it offers no guidance on when to prefer this over log_time_bulk, timesheet, or update_time_entry, which is the primary routing decision among siblings.

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