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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds the useful detail that results are labor cost as well as hours and are grouped by employee/day/cost code. It says nothing about aggregation rules, whether all time cards or only approved ones are included, or volume/pagination.

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 that packs scope, metric, and grain with no filler. Nothing is repeated and nothing extraneous is included.

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 three-parameter read-only reporting tool with rich annotations and no output schema, the description conveys enough: what is returned, at what grain, and for what scope. A note on aggregation or data freshness would be the only missing piece.

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 each parameter documented including format and a pointer to list_projects for the id, so the baseline is 3. The description's 'per employee and per day and cost code' hints at the output grain but adds no semantics about the date parameters beyond what the schema states.

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 the resource precisely: hours and labor cost for a single project, broken down per employee, per day, and per cost code. The grain of the data is stated, which meaningfully distinguishes it from a flat list of time cards. It does not name the neighboring tools (list_time_cards, get_job_costing) it should be contrasted with, so it falls 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?

Usage is only implied: the required project_id and the start_date/end_date filters suggest a single-project date-range query. There is no explicit 'use this instead of X when...' statement, nor any exclusion guidance against list_time_cards or get_job_costing, which cover adjacent concepts.

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