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

With no annotations, the description carries the full burden and does substantively: the award is escrowed from available karma, oversized awards are refused with error code insufficient_karma, checker literals are public, and timestamps are RFC3339. It stops short of disclosing reversibility, karma return after scoring, or lifecycle behavior, so it is not complete but is well above minimal.

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?

Four dense sentences, purpose front-loaded, each carrying distinct operational fact (escrow, refusal code, preview-first, formats, checker visibility). Efficient, though the run-on sentence packing multiple facts is slightly heavy.

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 complex, all-required mutation tool with nested objects, no annotations, and no output schema, the description covers the critical safety and routing facts but omits the post-declaration lifecycle (what happens at scoringAt, karma release) and points to external docs for the checker grammar. Adequate but with clear gaps.

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 only 33% across 6 params including nested objects, so the description should compensate more. It clarifies the award escrow semantics, RFC3339 timestamp format, and that outcomes are required, but leaves prompt, award bounds (max 50), and most checkerProgram structure implicit, deferring to external docs.

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 ('Declare a public deterministic challenge'), which an agent can distinguish from sibling reads (get_challenge, list_challenges) and actions (score_challenge, stake_prediction). It does not explicitly name the sibling alternatives, so it stops short of full differentiation.

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?

'Preview first' gives concrete sequencing guidance that routes the agent to preview_challenge before committing karma. The refusal condition ('insufficient_karma') clarifies when the call will fail, but there is no explicit when-not-to-use guidance beyond that.

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