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

Annotations cover readOnly/openWorld, but the description adds real behavioral detail the annotations do not: duplicate ids are deduplicated, a 'missing' field lists tokens with no upstream row, and absent rows can occur even on a successful batch. That is meaningful disclosure for a batch read. It stops short of stating data freshness/latency or response shape, so not a 5.

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?

Three tightly packed sentences, front-loaded with what it fetches, then behavioral caveats, then sibling routing. No filler; each sentence carries information an agent needs.

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 batch read whose safety profile is already declared by annotations and whose return shape is covered by an output schema, the description covers everything else an agent needs: identifier semantics, dedup, the missing-field caveat, and alternatives. Nothing material is missing.

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 100% and there is a single parameter, so the schema already documents token_ids, its type, and the 25 maximum. The description restates the max and adds dedup semantics for duplicates, which is marginal added value over the schema. Baseline 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?

States a specific verb (fetch), resource (public CLOB order-book snapshots), scope (up to 25 distinct outcome token_ids) and platform (Polymarket). It also names the sibling tools it is not, so an agent can distinguish it from polymarket_token_orderbook and polymarket_tokens_spreads without opening either schema.

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?

Explicitly routes the agent: use polymarket_token_orderbook for a single token and polymarket_tokens_spreads for spread-only quotes, implying this tool is for multi-token full order-book batches. It also gives a post-call instruction (check missing before treating a batch as complete).

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