Create post (legacy)

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

Annotations already declare readOnly=false, destructive=false, openWorld=true, so the safety profile is covered. The description adds that execution is synchronous and that it is the legacy API, which is genuinely useful behavioral context versus the async job path, but nothing about auth needs, rate limits, or side effects.

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, front-loaded with the action and scope, followed immediately by the preferred alternative. Zero filler.

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 2-param mutation with a complex nested payload and no output schema, the description covers purpose and the preferred alternative but says nothing about the return value of the synchronous call or the meaning of profile_id. Adequate given the rich data schema and annotations, but with gaps.

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 nested data field is richly documented (types, content array, call_to_action enum values), but profile_id carries no description and the tool description adds no parameter detail of its own. Given the thorough schema for data, baseline 3 is appropriate, though it does not compensate for the undocumented profile_id.

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 (Create) and resource (a post on a profile), and explicitly flags it as the legacy sync API. It names the sibling it relates to (reddit_ads_create_post_job), so an agent can distinguish it from the job-based path without opening a schema.

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?

"Prefer reddit_ads_create_post_job" gives explicit routing to the alternative and a clear preference signal. It does not fully spell out the narrow cases where the legacy sync path is still appropriate, but the primary when-to-use guidance is present.

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