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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds the returned field set, which is genuinely useful given there is no output schema, but says nothing about the hydrated flag's effect, permissions, or error behavior.

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?

Two compact fragments with the resource and payload front-loaded; little waste. The trailing REST path is mildly redundant but gives an agent a concrete anchor.

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 no output schema, listing the returned fields is the right compensation and largely closes the gap. What remains unstated is the default hydration behavior and whether related objects are embedded without hydrated=true, which matters for interpreting the response.

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%, with hydrated (embed project/task/tags), workspace_id (default active workspace) and time_entry_id fully documented inline, so the baseline of 3 applies. The description adds no syntax or behavioral detail beyond the schema.

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?

Names the resource and the identifier key ('One time entry by id') and enumerates the payload fields (description, project, task, tags, billable, rates, custom fields, timeInterval), plus the underlying endpoint. It reads clearly against list_time_entries/update_time_entry, though the differentiation is implied by 'by id' rather than stated.

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?

There is no statement of when to use this tool versus alternatives, no mention of prerequisites (e.g. needing a valid time_entry_id or workspace context), and no exclusions. The only routing hint lives in the schema, not the description.

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