Polymarket midpoint price (CLOB)

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

Annotations cover readOnlyHint, idempotentHint, destructiveHint, and openWorldHint, providing a solid safety profile. The description adds that it returns the current midpoint and clarifies the token_id source (from a market's clobTokenIds). It does not contradict annotations and provides useful context beyond them.

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 description is one clear sentence plus a concise example. It is front-loaded with the main purpose and contains no extraneous words. Every element serves a purpose.

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 simple tool with one parameter and no output schema, the description is mostly complete. It explains the main purpose, parameter source, and gives an example. However, it does not specify the output format (e.g., decimal or wei), which could be helpful given the absence of an output schema.

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%, so baseline is 3. The description enhances the parameter semantics by explaining that token_id is a CLOB token id from a market's clobTokenIds and provides a concrete example, which adds value beyond the schema's minimal 'CLOB token id' description.

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 clearly states the tool returns the current midpoint (mid of best bid/ask) for an outcome token. It specifies the resource (outcome token) and the action (get midpoint price), and distinguishes from sibling Polymarket tools like last_trade_price, order_book, and spread.

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 does not provide guidance on when to use this tool versus alternatives. While sibling tools are listed, the description lacks explicit when-to-use or when-not-to-use advice, such as suggesting polymarket_last_trade_price for last trade price or polymarket_order_book for full order book depth.

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