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

With no annotations, the description must carry the behavioral load; 'Returns' implies a safe read and the 24-hour lookback is disclosed. However, it omits how movement is measured (percent vs absolute), the sort order, whether results are capped, and any rate-limit or auth behavior, leaving meaningful gaps for a zero-annotation tool.

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 well-formed sentence with the selection criterion front-loaded and zero filler. Its brevity is appropriate even if it leaves detail on the table elsewhere.

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?

There is no output schema and no annotations, and all three parameters are schema-documented, so the description is close to sufficient. It still lacks the definition of 'largest movement' and result ordering, which an agent would want to describe results correctly to a user.

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%, with limit, direction (enum), and notification_message all documented, so the schema does the heavy lifting and baseline 3 applies. The description adds no semantics about what 'limit' counts against or how direction interacts with the mover ranking.

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 Polymarket markets') plus the selection criterion ('largest price movements in the last 24 hours'), which separates it from siblings like get_price_history or get_market_odds. It does not explicitly name an alternative or boundary tool, so it stops short of 5.

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 reach for this tool versus get_arbitrage_opportunities, get_whale_trades, or get_price_history, and no prerequisites or exclusions are stated. The use case ('what moved today') must be inferred entirely from the description's noun phrase.

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