List posts

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds only that this hits a legacy API endpoint, which is genuinely useful context, but says nothing about pagination behavior or return shape beyond what the schema already documents.

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?

A single tight sentence with no waste and the scope front-loaded. It is perhaps overly terse given the tool's six parameters, but nothing is padded.

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 6-parameter list tool with no output schema and half the schema undocumented, one sentence is not enough. An agent gets no help on filtering semantics, pagination strategy, or how the legacy results differ from structured posts.

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 only 50% – type, source, and profile_id have no descriptions, and the description adds no parameter meaning at all. It does not compensate for the gap by explaining the enum filters or what profile_id accepts.

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 (list) and resource (posts) scoped to a profile, and the '(legacy posts API)' qualifier hints at how it differs from reddit_ads_list_structured_posts. It is clear but does not explicitly name the sibling to use instead, so the differentiation is left partly to inference.

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 parenthetical '(legacy posts API)' is the only hint about when to use this over reddit_ads_list_structured_posts, and it never states that condition explicitly. No prerequisites, no when-not guidance, no alternative named.

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