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

Annotations only cover the generic safety profile (not read-only, not destructive, not idempotent). The description adds genuinely new behavior: nothing is created on an ad platform and nothing is spent, and moderation-flagged content still creates the idea but holds it from public surfaces with heldForReview reported.

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?

Front-loads the core action, then usage, then args, then returns, then the moderation caveat. Each block earns its place; the args list adds semantic detail the schema lacks rather than restating types.

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?

With no output schema, the explicit returns object (id, name, summary, publicSlug, heldForReview, workbenchUrl, nextStep) is valuable, and the moderation/spend behavior is covered. Minor gaps remain: no mention of permissions, rate limits, or the response_format parameter.

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 0%, so the description carries the burden and does so for the three meaningful params — name, summary (what it is/who it's for/problem solved), and websiteUrl (live URL for ad traffic). response_format is left undocumented, though its enum makes it largely self-evident.

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?

States a specific verb and resource with scope: 'Create a new idea in the signed-in user's workspace.' It further distinguishes two creation modes (validation test vs. ads for something already shipped), making it clearly distinct from the get_/list_/update_ siblings.

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?

Gives explicit when-to-use guidance and a branching condition: start a validation test, or pass websiteUrl to set up ads for an already-shipped product. It does not name an alternative tool or state when-not to use it, so it stops short of a 5.

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