threads_list_posts

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

Annotations only say readOnlyHint=true; the description adds real behavioral context beyond that, notably that an empty items array is not proof of the end of the list, and that reposts surface with media_type=REPOST_FACADE. It does not cover rate limits, ordering, or per-post visibility filtering, which keeps it below 5.

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 core action, then ordered as prerequisites, pagination, exclusions, and return-field quirks. Every sentence carries operational information; nothing is 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?

An output schema exists, so the description need not explain full return shapes, yet it still flags the tricky fields and the paging termination rule that an agent would otherwise get wrong. Gaps are minor: no limit-tuning advice and no statement about ordering or date filtering.

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 0%, so the description must carry parameter meaning and it largely does: account_id's source is given, and after is tied to next_cursor with its null-termination semantics explained. limit is never discussed in prose, though its bounds and default are still structurally visible in the schema.

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?

A specific verb and resource with scope stated: reading one page of the connected account's *own* posts, plus an explicit exclusion ('Replies to other people's posts are not included'). It distinguishes the tool from the reply-listing siblings by scope, but never names the sibling to use instead, so it stops just short of a 5.

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 a clear precondition ('Get account_id from threads_list_accounts') and a concrete paging loop: pass the previous response's next_cursor as after, with null marking the end. It does not name alternative tools for conversation or replies, so the when-not side is implied by the exclusion rather than stated.

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