ga4_update_key_event

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

No annotations provided, so description carries full burden. It clarifies the write nature, partial update behavior, and requirement of confirm flag. However, it does not disclose idempotency, error conditions, or immutable fields. Adequate but not deep.

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 and a prerequisite clause. Every phrase carries information: the operation, examples, partial update behavior, and conditions. No fluff, front-loaded with key verb and scope.

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 5 parameters, no output schema, and no annotations, the description covers the operation type, partial update guidance, and prerequisites. Could mention response format or error handling, but the current level is sufficient for a straightforward 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 80%. Description adds value by explaining that 'body' merges over typed fields and when to use it (nested/advanced). For updateMask, says 'Omit to derive from the supplied fields'. Provides example parameter 'countingMethod'. Adds context beyond the 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 starts with '[GA4 WRITE]' and states 'Update a key event', clearly identifying the verb and resource. Examples like 'counting method or default value' specify scope. Distinguishes from siblings like ga4_create_key_event and ga4_delete_key_event.

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?

Explicitly says 'Pass only the fields to change' and explains updateMask derivation. Lists prerequisites (GA4_MCP_ENABLE_WRITES=true, confirm=true). Lacks explicit when-not-to-use or alternatives, but the sibling set makes the context clear.

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