ga_list_data_streams

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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds context that the tool is the path to measurement IDs, but does not disclose additional behavioral details such as pagination, quotas, or error conditions; given the rich annotations, this is acceptable.

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 short sentences carry clear action, scope, and purpose with no filler. The main statement is front-loaded and the usage hint follows immediately.

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 single-optional-parameter read-only list tool, the description is sufficient: it names the resource, the default scope, the override, and the intended use. The return value is strongly implied through 'find measurement IDs,' so the lack of an output schema does not create a gap.

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 100%, and the propertyId parameter is already well documented with format, default behavior, and discovery guidance. The tool description itself does not need to add parameter detail, so baseline 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 uses a specific verb and resource: 'List data streams for the configured GA4 property.' It also gives a concrete downstream purpose (finding measurement IDs for Measurement Protocol), which distinguishes this listing tool from sibling tools that list accounts, properties, dimensions, metrics, or key events.

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 says when to use it: when measurement IDs are needed for Measurement Protocol. It does not name exclusions or alternatives, but the use case is clear enough for an agent to select this over sibling list tools.

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