ServiceNow MCP Server

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

No annotations are provided, so the description must fully disclose behavioral traits. It only states the action 'update' without indicating whether this is a mutation, what permissions are required, if changes are reversible, or what the response looks like. For a tool that modifies data, this lack of transparency is critical.

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 a single, straightforward sentence that is front-loaded with the core action. There's no unnecessary verbiage, making it efficient. However, its brevity contributes to underspecification rather than optimal clarity.

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 complexity of updating a catalog item variable with 1 required parameter and multiple optional fields, no annotations, and no output schema, the description is severely incomplete. It fails to explain what the tool does beyond the basic verb, leaving the agent without necessary context for effective use.

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 0%, meaning parameters are undocumented in the schema. The description adds no information about parameters beyond implying an update action. It doesn't mention the required 'variable_id' or optional fields like 'label' or 'mandatory', leaving the agent unable to understand what inputs are needed.

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 'Update a catalog item variable' restates the tool name with minimal elaboration. It specifies the verb 'update' and resource 'catalog item variable', but lacks detail on what a catalog item variable is or what aspects can be updated. Compared to siblings like 'update_catalog_item' or 'update_workflow_activity', it doesn't differentiate scope or functionality.

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?

No guidance is provided on when to use this tool versus alternatives. The description doesn't mention prerequisites (e.g., needing a variable_id), when not to use it, or related tools like 'create_catalog_item_variable' or 'list_catalog_item_variables'. This leaves the agent without context for tool selection.

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