update_time_entry

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

Discloses a non-obvious behavioral trait beyond the annotations: Gryzzly's update requires all fields, so omitted values are 'read back from the existing entry first,' i.e., a read-modify-write merge. Annotations already cover safety (readOnly=false, idempotent=true, destructive=false), so this adds genuine value; it does not mention permission needs or concurrency.

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?

Front-loaded with the verb and reasonably sized, but the sentence 'by the id list_time_entries returns: its duration...' is run-on and awkward to parse, mixing the identifier source with the field list in a way that requires re-reading.

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?

An output schema exists, so return values need not be explained, and the annotations cover the safety profile. The description supplies the routing (log_time/delete_time_entry) and the partial-update semantics, making it largely complete, though it omits auth/permission context for editing another user's entry.

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% and each parameter already carries a description including 'Left alone when absent,' so the schema does the heavy lifting. The description reinforces the absent-field behavior but adds little beyond it, and never mentions the user/project params, so the baseline 3 holds.

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 ('Change one time entry'), names the returned identifier source (list_time_entries), and enumerates the mutable fields (duration, day, task, description). It also names the sibling tools log_time and delete_time_entry, letting the agent distinguish this update tool from the add/remove alternatives without opening a 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?

Explicitly routes the agent to alternatives: 'Use log_time to add time and delete_time_entry to remove an entry,' which clarifies this is neither creation nor deletion. It gives clear context for use but stops short of stating when-not conditions or prerequisites (e.g., permissions on others' entries).

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