list_challengers

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

With no annotations, the description carries the burden of behavioral disclosure. It clearly reveals authentication and access requirements, including that setting PROOF_API_KEY and restarting the server is necessary. It also clarifies a non-obvious boundary: start_login does not unlock this tool. Since this is a read-only list operation, the absence of side-effect warnings is acceptable.

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?

The description is compact and front-loaded: the core purpose appears in the first sentence, and the access prerequisites follow in a clearly separated block. Every sentence adds necessary information with no filler.

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 one-parameter list tool, the description covers the essential context: what is listed, the scope, and the access prerequisites. It does not describe the output format or pagination, but no output schema exists and the list semantics are reasonably inferable. The access note adds significant completeness beyond the bare schema.

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?

The schema already fully documents the single parameter hitl_id with type, pattern, and description 'HITL config ID'. The description adds no new parameter-level detail beyond repeating 'HITL config' in the purpose. With 100% schema coverage, the baseline 3 is appropriate.

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 clearly states the operation: 'List the Proof-Me challengers enrolled on a HITL config.' It names a specific verb, resource type, and scope. This distinguishes it from challenger-related mutations like add_challenger, invite_challenger, and remove_challenger.

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 gives actionable usage context: a Proof account is required, PROOF_API_KEY must be set, and the server must be restarted before calling again. It also explicitly warns that start_login does NOT open this tool, preventing a likely misstep. It does not name alternative list tools, but none directly overlap with this operation.

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