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

Annotations already declare readOnly, openWorld, and idempotent hints, lowering the burden. The description goes well beyond this by disclosing the real cost per call ($0.005 USDC), the x402 payment mechanism, the unpaid-call behavior, the no-data-no-cost guarantee, and the play-money/MANA token semantics. This is rich, actionable behavioral context that structured fields could not convey.

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 main function is front-loaded in the first sentence, followed by essential caveats (play-money, cost, payment failure mode) and an HTTP equivalent. Each sentence carries distinct information, and there is no redundant or filler content.

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?

Here we have no output schema, so the description carries the full burden of explaining returns; it does so by listing all returned fields. It also covers payment cost, the no-cost-on-no-data behavior, token reporting, and the HTTP route. For this simple read-only listing tool, everything needed to invoke and interpret the response is present.

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 100%, so all four parameters (sort, limit, filter, search) are already documented with examples. The description adds no additional parameter-level meaning beyond implying that 'search' maps to question text, so the baseline score of 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 opens with a specific verb and resource: 'Search or browse Manifold Markets questions', and enumerates the exact returned fields (probability, outcome type, volume, liquidity, unique bettor count, close time, creator, resolution state). This clearly distinguishes it from sibling Polymarket and prediction-market tools by naming the Manifold venue, making the tool's purpose unambiguous.

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 makes it clear the tool is for Manifold Markets questions, giving an agent sufficient context to select it when Manifold-specific data is needed. However, it does not explicitly name alternatives or state when not to use it, such as directing to polymarket_markets for Polymarket or prediction_market_search for cross-venue searches.

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