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

With no annotations, the description carries the full burden and does deliver real behavior: entries enter an approval workflow ('waits for approval like clocked time'), overlap with the person's other time is rejected, and duration is capped at 24 hours. It omits permissions/scope requirements and what an overlap rejection looks like, but the core mutation semantics are disclosed.

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 sentences, no waste, with the identity of the operation front-loaded and the two constraints (approval, no overlap) following. Nothing repeats the schema or the title.

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 needn't be explained, and the approval/overlap/24-hour behaviors are covered. But for a mutation with zero annotation coverage and eight parameters at 25% schema coverage, the definition leaves the agent without guidance on required context (job vs shop vs visit) and failure modes.

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 25%, so the description must compensate — and it largely doesn't. It implies started_at/ended_at (with a 24-hour maximum) and hints at person_id via 'the person's other time', but job_id, shop_id, visit_id, notes, and the category-conditioned requirement of job_id are left entirely to 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?

The description names a specific action ('Add time after the fact') on a specific resource (a manual time entry) and defines its scope: a start/end pair capped at 24 hours. The phrase 'after the fact' implicitly separates it from the live-clock siblings (timesheets_clockIn/clockOut), so an agent can route correctly without reading either 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?

'After the fact' implies the usage context (retroactive entry), but no explicit condition or named alternative is given. Nothing tells the agent when to prefer timesheets_update, timesheets_reopen, or clock-in siblings instead, so the routing signal is inferred rather than stated.

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