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

Annotations already declare destructive=true, idempotent=true and openWorld=true, so the safety profile is covered. The description still adds real context beyond that: downstream impact on payroll and invoicing, and that the operation is reversible via reopen, plus the underlying POST endpoint. It does not describe error/failure behavior, but the added value is substantive.

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 tight sentences, front-loaded with a "WRITE:" marker that signals mutation immediately, followed by meaning, consequences, recovery path and endpoint. Nothing is redundant.

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 2-parameter mutation with rich annotations and no output schema, the description supplies what an agent needs: effect, blast radius (payroll/invoicing), and reversibility. Minor gap is the absence of any note on failure modes (e.g. terminating an already-terminated or invoiced job).

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% and both parameters (job_id, end_date with yyyy-mm-dd pattern) are documented in the schema. The description reinforces that the date is the termination date, but adds no syntax or edge-case detail beyond the schema, so the baseline 3 applies.

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 ("ends a contract job") plus the effective date, and the parenthetical defines the operational meaning (contractor no longer placed, no further timecards). It is clearly separable from bilflo_reopen_contract_job and bilflo_update_contract_job, which appear as siblings.

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?

The description makes the use case clear (ending a placement on a date) and names the reversal path, bilflo_reopen_contract_job, so an agent knows the escape hatch exists. It stops short of stating explicit preconditions or when to prefer update_contract_job over termination.

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