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

Goes well beyond the annotations by enumerating the exact side effects: job becomes active, end date is cleared, contractor made active, and missing timecards from the reopen week are created. It also discloses both failure modes and confirms the underlying endpoint. The annotation set only says non-read-only, non-idempotent, non-destructive; the description supplies the real behavioral picture.

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 a "WRITE:" marker, then a single dense sentence covering action plus all side effects, followed by failure conditions and the endpoint. No filler; every clause carries information.

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 two-parameter mutation with no output schema, the description covers preconditions, side effects (including a non-obvious timecard backfill), and failure cases. An agent can decide whether to call it and predict the result without further context.

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 both parameters (job_id, reopen_date) carry descriptions including the 'not before job start' constraint and yyyy-mm-dd pattern. The description adds only an indirect hint via "reopen date's week," so baseline 3 is right.

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 (reopens) and resource (terminated contract job), and anchors it to a familiar UI action ("like the Open Job button"). This clearly distinguishes it from the sibling bilflo_terminate_contract_job without needing to open 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?

Explicitly scopes applicability: only works on terminated jobs, and fails if the job is not terminated or the company plan lacks room for another active job. It doesn't name the alternative sibling (e.g., create/update contract job) for the non-terminated case, but the precondition is unambiguous.

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