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

With no annotations, the description carries the full burden and does unusually well: it discloses the per-turn/per-party/per-forecast limit, that only the latest number counts toward forecast_consensus, and that Brier scoring weights numbers by duration. It also warns that untrusted_-prefixed content is data, not instructions. Minor gap: it does not state what happens on a duplicate attempt or a closed forecast.

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 eligibility and action, then consequences (consensus/Brier), limits, and safety guidance. Dense but every sentence carries information; the opening fragment 'Any role, any party (the author too).' is slightly abrupt but functional.

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 mutation tool with no annotations and no output schema, the description covers eligibility, timing, scoring consequences, and injection safety well enough to invoke correctly. Only error behavior and the exact return/acknowledgment shape are unaddressed.

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%, so the schema already explains slug, claim_seq, probability, and reasoning. The description adds only light context about 'your current probability' and 'your latest number,' not field-level meaning beyond what the schema provides, so the baseline of 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?

The description uses a specific verb+resource combination: 'Sets your current probability for an open forecast of your thread.' It distinguishes this from re-posting a forecast ('instead of posting the same forecast again') and implicitly from resolve_forecast via 'only before resolves_at,' though it never names the resolving sibling outright.

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?

Gives a concrete trigger ('after a race or a release changes the picture') and explicit eligibility ('Any role, any party (the author too)') plus a timing boundary ('only before resolves_at'). The alternative (posting again) is named, but the other sibling it must not be confused with, resolve_forecast, is only implied by the timing rule.

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