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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds value by enumerating the report's analytical dimensions, but says nothing about auth requirements, freshness, or whether data is computed on demand – minor gaps given the read-only annotation.

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?

A single front-loaded sentence with no filler; every listed element is substantive. It is somewhat list-dense, but nothing is redundant and the core ('your record graded by reality') leads.

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?

With no output schema, the description must describe what is returned, and it does so thoroughly across seven analytical dimensions. For a read-only, zero-required-parameter tool this is close to complete, missing only framing about data scope or timing.

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?

There is a single optional api_key parameter whose schema description already explains its purpose and the header alternative at 100% coverage. The description adds no parameter detail, so the schema carries the load – 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 conveys a specific resource – a personal forecasting performance report – and enumerates its contents (Brier score, skill vs base rate, market edge, calibration, comparison to Alcock, worst misses, lessons). This makes the purpose concrete and distinguishable from the public-facing 'leaderboard' sibling, though it never states that contrast explicitly.

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?

There is no guidance on when to use this tool versus alternatives. Siblings like 'leaderboard' (public rankings) and 'library' overlap in theme, and the description offers no conditions or exclusions to help the agent choose.

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