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

Annotations already establish this as a safe read operation (readOnlyHint=true, destructiveHint=false). The description adds useful behavioral context by specifying that it returns full creative content—hooks, script, prompts—rather than a summary or stats. It does not cover error behavior for missing ads or rate limits, but with annotations carrying the safety profile this is reasonably transparent.

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, front-loaded with what the tool returns and followed by when to use it. Every phrase carries information; there is no redundant restatement of the tool name or 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 simple one-parameter read with full schema coverage and read-only annotations, the definition gives enough for correct invocation: it explains the content returned and the logical sequence after list_ads. Absent an output schema, it helpfully lists the main return components, though it could mention not-found behavior.

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 single adId parameter is already documented as coming from list_ads. The description reinforces the list_ads dependency but adds no format or validation meaning beyond the schema. Baseline 3 is appropriate when the schema fully handles parameter semantics.

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 states a specific retrieval action ('One ad in full') and enumerates the content returned: hooks, scene-by-scene script, and model-native prompts. This clearly distinguishes it from list_ads and get_ad_stats, which siblings handle listing and metrics rather than full creative content.

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?

It gives explicit sequencing and intent: 'Use after list_ads when the user wants the actual content.' That tells the agent both the prerequisite context and the condition for choosing this tool. It stops short of saying when not to use it or naming alternatives beyond list_ads, but the guidance is clear.

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