ga4_create_data_stream

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 labels the operation as a WRITE and mentions prerequisites, but fails to describe side effects, idempotency, error conditions, or what happens on success. This is insufficient for a mutation tool with no annotations.

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 that is immediate and to the point, with a clear tag upfront. It contains no fluff and efficiently conveys the core purpose and key requirement.

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?

For a tool with 8 parameters, no output schema, and no annotations, the description is minimal. It covers the basic purpose and requirement but does not explain parameter dependencies (e.g., which parameters apply to which stream type) or describe the response format. Context is adequate but incomplete.

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 88%, so the schema already documents most parameters well. The description adds value by listing the supported stream types (web, Android, iOS) and reiterating the confirm requirement, but does not provide new parameter semantics beyond what the schema offers. Baseline of 3 is appropriate.

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 explicitly states 'Create a data stream' with the specific resources web, Android, and iOS, clearly defining the tool's action and target. The [GA4 WRITE] tag further clarifies the operation type, and the tool name itself distinguishes it from sibling tools like ga4_update_data_stream and ga4_delete_data_stream.

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 includes clear prerequisites: 'Requires GA4_MCP_ENABLE_WRITES=true and confirm=true.' This tells the agent when the tool can be used. However, it does not explicitly mention when not to use it (e.g., for updates) or list alternative tools, though the sibling list provides context.

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