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

Annotations already establish readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds genuinely useful behavioral context beyond that: forecasts are 'public' only, 'latest' rather than historical, and 'compact' (summarized) rather than full records, and they are grouped 'by aggregation method'.

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 tight sentence with no filler, front-loaded with the verb and the key qualifiers. Nothing to trim.

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 an output schema present, return values need no explanation, and the one-parameter read-only surface is simple. The description is nearly complete; the only real gap is routing guidance against the forecast_history sibling.

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?

Only one parameter, and the schema already documents it at 100% coverage with 'Metaculus question or post id'. The description's 'for one Metaculus question' merely restates that scope and adds no format or syntax detail. Baseline 3 when the schema does the work.

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: 'Returns ... forecast summaries ... for one Metaculus question'. The qualifiers 'compact public latest' and 'by aggregation method' give a precise sense of what is returned, distinguishing it from a raw history tool, though it never names the sibling metaculus_question_forecast_history 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?

The word 'latest' implies this is for current forecasts rather than time-series history, which is an implicit routing signal. But there is no explicit when-to-use statement, no exclusion, and no mention of the forecast_history sibling that an agent would need to choose between them.

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