user_permissions_update

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

Described as a write operation with replacement semantics ('API replaces the record'). Prerequisite flags are stated. No annotations provided, so description partially covers behavior, but lacks mention of rate limits or auth details.

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?

Two sentences, no fluff. The purpose and key usage guidelines are immediately clear. The [WRITE] indicator helps quick scanning.

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?

Covers the write nature, prerequisites, and replacement behavior. No output schema, so return values are not explained, but overall adequate for a simple update 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?

Schema coverage is 100% with descriptions for each parameter. The description adds important context: 'Provide the full intended access...as the API replaces the record,' which clarifies how to use containerAccess and accountPermission.

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 is for updating user account and/or container access levels, with a [WRITE] prefix. It distinguishes from siblings like get, create, delete.

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 explicitly lists prerequisites (GTM_MCP_ENABLE_WRITES, confirm=true) and advises providing the full intended access. However, it does not mention when not to use or compare with alternatives explicitly.

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