prediction_markets

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

With no annotations, the description carries the full burden and does disclose non-obvious traits: a per-call cost of $0.009 USDC, a p99 latency of 3000ms, and the filter that only open markets are returned. It could say more about rate limits or result stability, but the cost/latency/scope disclosures are genuinely useful.

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 the resource and return fields, then usage, then constraints, then cost/latency. The 'Params:' sentence largely duplicates schema metadata, which is minor waste, but the overall structure is tight and scannable.

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 2-param, zero-required read tool with no output schema, the description covers purpose, usage modes, return fields, cost, latency and the open-markets constraint. An agent has enough to invoke it correctly; only edge cases like empty-result behavior 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 50%: the query parameter is already documented in the schema, while limit has only structured min/max/default. The description restates limit's range and default (redundant with the schema) and adds little on query beyond the schema's own example. Baseline 3 is appropriate given the partial coverage.

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 names a specific verb (live search/listing of Polymarket prediction markets) and enumerates exactly what is returned: outcome probabilities, 24h volume, liquidity, 24h price change and end date. No sibling tool covers prediction markets, so the resource is 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?

It explicitly states two usage modes: pass a topic query (with examples like 'bitcoin', 'election', 'fed rate') or omit query to get the highest-volume markets. It also flags that only open markets are returned. It does not name a competing alternative, but none exists among siblings, so this is strong contextual guidance.

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