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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds that the spread is 'public' and CLOB-sourced, a small piece of context, but says nothing about freshness, precision, or edge cases like empty books. Modest value beyond structured fields.

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, front-loaded sentence with no filler; the resource and scope are stated immediately. Efficient, though it is bare enough that it could have carried one clause of routing guidance at no real length cost.

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?

An output schema exists, so return values need not be explained, and the input is fully documented. However, for a token-level metric tool living among many polymarket token endpoints, the absence of any statement about how it relates to orderbook/midpoint/batch siblings leaves a routing gap.

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% for the single token_id parameter, and the description adds no syntax or format detail beyond what the schema already documents. Baseline 3 is appropriate 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 (Returns), resource (public CLOB spread), and scope (one token id), so an agent can identify it as a per-token spread lookup. It does not name or distinguish itself from close siblings like polymarket_token_orderbook or polymarket_token_midpoint, so it stops short of a 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?

No when-to-use, prerequisites, or alternatives are given. With siblings such as polymarket_tokens_spreads (batch) and polymarket_token_orderbook, the description leaves the agent to infer when this single-token spread call is preferred.

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