Polymarket MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions 'public on-chain data' which implies read-only access, but doesn't cover other important aspects like rate limits, authentication requirements, pagination behavior (beyond the schema parameters), error conditions, or response format. This is a significant gap for a tool with 4 parameters.

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 appropriately concise with two sentences: one stating the purpose and one providing usage guidance with an example. It's front-loaded with the core functionality. The example could be slightly more informative, but overall there's minimal waste.

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 tool with 4 parameters, no annotations, and no output schema, the description is insufficient. It doesn't explain what the tool returns (positions format, data structure), error handling, rate limits, or authentication requirements. The lack of output schema means the description should compensate by explaining return values, which it doesn't do.

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%, so the schema already documents all 4 parameters thoroughly. The description adds minimal value by mentioning 'user address' and 'optional market conditionId' with an example, but doesn't provide additional semantic context beyond what's in the schema. This meets the baseline for high schema coverage.

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 a user's open positions (public on-chain data).' It specifies the resource (open positions) and the data source (public on-chain), but doesn't explicitly differentiate from sibling tools like 'get_closed_positions' or 'get_positions_value' beyond the 'open' qualifier.

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 with 'Use user address; optional market conditionId' and an example, but doesn't explicitly state when to use this tool versus alternatives like 'get_closed_positions' or 'get_positions_value'. The guidance is implied rather than explicit.

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