threads_list_pending_replies

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

readOnlyHint=true already establishes the safety profile, and the description still adds genuine context: an auth scope requirement (threads_read_replies), the approvals-enabled precondition, the pagination loop ('pass next_cursor as after until it is null'), the empty-page-with-cursor edge case, and an explicit prompt-injection warning about reply text.

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 purpose then preconditions, prerequisites, and pagination in a logical order; nearly every sentence earns its place. Minor cost: the enable_reply_approvals reference names a parameter belonging to a publish sibling, which briefly muddies an otherwise tight read.

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 an output schema present, return-value documentation is unnecessary, and the description instead covers the things the schema cannot: auth scope, the approvals precondition, the pagination termination rule, and injection safety. Nothing an agent needs to call this correctly is missing.

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 0%, so the description carries the burden, and it does for post_id (numeric parent post ID), approval_status (omit for both states, or pending/ignored), and after (next_cursor until null). account_id and limit are left unexplained, which prevents a 5 given the complete absence of schema documentation.

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?

Opens with a specific verb and resource: 'Read one page of pending/ignored replies under an own post with reply approvals.' The scope qualifiers (own post, reply approvals) plus the cited sibling threads_moderate_reply make it distinguishable from threads_list_replies without opening either 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?

Gives explicit preconditions ('The parent must have reply approvals enabled; an ordinary post is not an empty approval queue'), explicit fallbacks ('choose another post or use enable_reply_approvals=true'), the value-fork for approval_status, and a hard rule that the sibling threads_moderate_reply is only used after user approval.

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