ChartMogul 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. It discloses that the tool mutates data (adds attributes) and returns updated attributes, but does not mention permissions, rate limits, error conditions, or whether the operation is idempotent. It adds some behavioral context (e.g., default source value) but is incomplete for a mutation tool.

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 sized and front-loaded with the core purpose. Every sentence adds necessary information (e.g., attribute structure, type details, return value). It could be slightly more structured but avoids redundancy and is efficient for the complexity.

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 no annotations and no output schema, the description does well on parameters but lacks completeness for a mutation tool. It explains what the tool does and the input details thoroughly, but does not cover behavioral aspects like side effects, error handling, or response format beyond 'Returns updated custom attributes', leaving gaps in contextual understanding.

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 has 0% description coverage, so the description fully compensates by detailing both parameters: 'uuid' (customer UUID) and 'custom_attributes' (array of objects with type, key, value, source). It provides extensive semantics including data types, formats, constraints, and examples, adding significant value beyond the bare schema.

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 ('Add custom attributes to customer') and resource ('customer'), distinguishing it from siblings like 'add_customer_tags' (which adds tags) or 'list_customer_attributes' (which lists attributes). The verb 'add' is precise and the scope is well-defined.

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 implies usage context by specifying the ChartMogul API and the need for a customer UUID and attribute array, but does not explicitly state when to use this tool versus alternatives like 'update_customer' or 'list_customer_attributes'. It provides necessary prerequisites but lacks explicit sibling differentiation.

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