mcp_update_user_meta

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

Without annotations, the description fails to disclose important behaviors like whether the update merges or overwrites meta, what happens on duplicate keys, or if it is destructive. The description adds no value beyond the tool's name.

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 but fails to provide necessary context. It is front-loaded but sacrifices completeness for brevity, making it adequate but not efficient.

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 lack of output schema and annotations, the description is incomplete. It does not explain return values, error handling, or behavior for nested objects, which is insufficient for a mutation tool.

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 input schema already thoroughly describes both parameters (id and meta). The description does not add additional meaning beyond what the schema provides, leading to a baseline score.

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 identifies the tool as updating user meta data, which is a specific action. However, it does not differentiate from sibling tools like mcp_update_user or mcp_get_user_meta, relying on the name for distinction.

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 such as mcp_update_user or mcp_set_option. The description lacks any context about prerequisites or situations where this tool is appropriate.

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