ChartMogul MCP Server

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

No annotations are provided, so the description carries full burden. It discloses that this is a mutation operation ('Update') and specifies what fields are modifiable (name, plans), which is useful. However, it doesn't describe permissions needed, whether changes are reversible, rate limits, error conditions, or what the 'updated plan group object' contains. For a mutation tool with zero annotation coverage, this leaves significant behavioral gaps.

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. Each sentence adds value: first states the action, second details modifiable fields with examples, third specifies return value, fourth lists required parameters. There's minimal waste, though the bracketed '[ChartMogul API]' prefix could be omitted as redundant if the server context is already known.

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 mutation tool with 2 parameters, no annotations, and no output schema, the description does an adequate job covering the basics: purpose, parameters, and return type. However, it lacks details on authentication requirements, error handling, side effects, and the structure of the returned object. Given the complexity of updating a resource with nested plans array, more behavioral context would be beneficial.

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?

With 0% schema description coverage, the description fully compensates by explaining both parameters: 'uuid' is required and identifies the plan group, and 'data' is a dict containing modifiable fields (name as string, plans as array of UUIDs). It provides concrete examples of plan UUID format ("pl_123...") and clarifies the structure, adding substantial 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 action ('Update plan group') and specifies the resource ('plan group'), which is a specific verb+resource combination. It distinguishes itself from siblings like 'create_plan_group' by focusing on modification rather than creation. However, it doesn't explicitly differentiate from other update tools like 'update_plan' or 'update_customer' beyond the resource name.

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 no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites, when-not scenarios, or compare with sibling tools like 'retrieve_plan_group' or 'list_plan_groups'. The only implicit usage context is that you need a plan group UUID to update, but this is stated as a requirement rather than guidance.

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