Polymarket MCP Server

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

With no annotations provided, the description carries full burden and adds valuable behavioral context: it specifies the API endpoint ('via CLOB /book'), error handling ('If token has no active order book, returns 404'), and data source constraints. This goes beyond the basic schema to inform the agent about operational behavior.

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 highly concise and front-loaded, with every sentence earning its place: it states the purpose, source, error condition, and example in three efficient sentences without redundancy or unnecessary detail.

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?

Given the tool's moderate complexity (single parameter, no output schema, no annotations), the description is nearly complete: it covers purpose, usage, behavior, and an example. However, it lacks details on return format (e.g., structure of order book data) which could aid the agent, slightly reducing completeness.

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%, so the schema already documents the token_id parameter. The description adds minimal semantics by referencing token_id in context and providing an example, but does not elaborate on format or constraints beyond what the schema implies. Baseline 3 is appropriate as the schema does the heavy lifting.

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 specific action ('Get order book'), resource ('via CLOB /book'), and target ('for token_id'), distinguishing it from siblings like get_batch_order_books (batch processing) or get_current_price (price only). It precisely defines the tool's function without ambiguity.

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 provides clear context on when to use it by specifying the source for token_id ('clobTokenIds from list_active_markets or get_market_details') and an example. However, it does not explicitly state when not to use it or name alternatives like get_batch_order_books for multiple tokens, leaving some guidance implicit.

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