Polymarket MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions 'public data,' which hints at accessibility without authentication, but doesn't clarify if this is a read-only operation, its rate limits, error handling, or what 'total markets' means (e.g., count, list). For a tool with no annotations, this leaves significant behavioral gaps, though it's not misleading.

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 extremely concise and front-loaded: it states the purpose in the first sentence and provides usage guidance and an example in the second. Every sentence earns its place with no wasted words, making it easy to parse quickly. The structure is efficient and clear.

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 simplicity (1 parameter, no output schema, no annotations), the description is adequate but has gaps. It covers the basic purpose and parameter usage, but lacks details on behavioral aspects (e.g., response format, error cases) and doesn't leverage the absence of annotations to provide more context. For a straightforward tool, it's minimally viable but could be more complete.

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?

The schema description coverage is 100%, with the parameter 'user' fully documented in the schema as 'User Ethereum address (0x...).' The description adds minimal value beyond this by providing an example ('Example: user=0xabc....'), but doesn't explain semantics like address validation or format beyond what the schema states. With high schema coverage, the baseline score of 3 is appropriate.

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's purpose: 'Get total markets a user has traded in (public data).' It specifies the verb ('Get'), resource ('total markets'), and scope ('a user has traded in'), though it doesn't explicitly differentiate from sibling tools like 'get_user_activity' or 'get_trades' which might provide related data. The purpose is specific and actionable.

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 some usage context by specifying 'Use user address' and giving an example, which implies when to use this tool—when you need aggregated trading data for a specific user. However, it doesn't explicitly state when to use this versus alternatives (e.g., 'get_user_activity' for detailed activity or 'get_trades' for individual trades), nor does it mention any prerequisites or exclusions. The guidance is implied but not comprehensive.

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