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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is covered. The description adds meaningful behavioral context: attribution is reported separately from causality, and unavailable spend/cost coverage stays explicit, which informs how an agent should interpret results. It also states the workspace scoping, going beyond the 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?

Two sentences, each earning its place: the first states the core function, the second adds a critical interpretative caveat. No filler or repetition of schema/annotations.

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 read-only, zero-parameter analytics tool without an output schema, the description tells an agent what data it will get (GTM analytics, verified commerce outcomes) and how to interpret it (attribution ≠ causality, explicit spend/cost gaps). Nothing necessary to invoke it correctly is missing.

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?

The input schema is empty and schema description coverage is 100%, so there are no parameters to document. Baseline for zero parameters is 4, and the description doesn't add parameter-specific detail because none exists.

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 begins with 'Read current PromptUI GTM channel analytics and workspace-scoped verified commerce outcomes,' naming a specific verb, resource, and scope. This clearly distinguishes it from siblings like gtm_generate_content and get_build_status, which serve different purposes.

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 establishes clear context: this is the tool for retrieving current analytics and commerce outcomes. It does not explicitly name alternatives or when-not-to-use, but the scoped wording ('current', 'workspace-scoped') implies the usage boundary. No exclusion guidance is provided, but none is needed given the obvious separation from content/build siblings.

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