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

With no annotations, the description carries the full burden, and it does disclose the key trait that this is read-only and that mutations live elsewhere. However, it says nothing about auth requirements, rate limits, pagination, or the shape of returned data, so behavioral coverage is only partial.

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-loaded with the read-only status statement followed by scope and routing guidance; three tight sentences. The 'Actions: current, history, performance' line mildly duplicates the schema enum but earns its place as scannable navigation.

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 and no annotations, the description does a reasonable job: it establishes read-only behavior, lists actions, and offloads parameter detail to adgpt_capabilities. It stops short of describing return values or the params object's shape, which the agent must fetch elsewhere.

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 50%. The description restates the three enum values already present in the schema and defers the meaning of the free-form params object to adgpt_capabilities, adding little beyond the structured fields.

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+resource: read-only status of a campaign's live ads, and enumerates the three sub-actions (current, history, performance). It distinguishes the read path from the write path by noting mutations happen in the web app, though it does not explicitly contrast itself against similarly-named sibling tools.

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?

Clearly scopes usage: this tool reads go-live status, while starting/renewing/stopping happens in the web app, and it tells the agent to consult adgpt_capabilities for action parameters. Missing an explicit statement of when 'current' vs 'history' vs 'performance' should each be chosen.

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