ga4_create_event_create_rule

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

With no annotations, the description carries the full burden. It discloses the write nature via '[GA4 WRITE]' and requires confirm=true, suggesting a safety check. It does not cover idempotency or error states, but the prerequisites are well-stated.

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 sentence with a prerequisite note, efficiently front-loading the write indicator and action. It is concise without redundancy, though it could benefit from slight restructuring for 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 no output schema and no annotations, the description is adequate but incomplete. It explains the core action and parameter usage but does not describe return values, success indicators, or error behaviors, leaving some gaps for a creation 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%, so baseline is 3. The description adds value by explaining 'body' is for 'eventConditions/parameterMutations', which is domain-specific context not in the schema, enhancing understanding beyond the raw schema description.

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 verb 'Create' and resource 'event-create rule on a data stream' with context 'server-side event creation'. It distinguishes this tool from siblings like ga4_delete_event_create_rule and ga4_update_event_create_rule.

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 mentions prerequisites (GA4_MCP_ENABLE_WRITES=true, confirm=true) but provides no guidance on when to use this tool vs alternatives like ga4_update_event_create_rule or when not to use it.

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