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

With no annotations at all, the description carries the full burden, and it does add one genuinely useful behavioral fact: 'Moves no credits' tells the agent this transition is financially inert. However it omits idempotency (what happens on a second start), error behavior for a wrong-state job, and permission requirements beyond what the schema's api_key field implies.

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 short sentences, zero filler, with the state transition and the credit-neutrality fact front-loaded. Every clause earns its place.

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 simple single-parameter state transition with no output schema and no annotations, the description supplies the essential semantics: who acts, what state change occurs, and that no funds move. Missing only failure-mode and idempotency notes, which are minor at this complexity.

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%: job_id is documented as 'A job you were awarded' and the deprecated api_key fallback is fully explained in the schema. The description adds no syntax, format, or constraint detail beyond that, so the baseline 3 is correct.

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 actor, verb, and resource ('Contractor starts an awarded job') plus the exact state transition (awarded → in progress), which lets an agent separate it from jobs_award, jobs_deliver, and jobs_cancel. It does not explicitly name those siblings, so it stops short of the 5 tier.

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 precondition is encoded in the transition arrow: the job must already be in 'awarded' state, and the caller must be the contractor. That is useful implied guidance, but no alternative tool is named and no explicit when-not condition (e.g. 'use jobs_deliver after work is done') is offered.

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