Change who can reply

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

Annotations declare the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), and the description adds the non-obvious behavior that existing replies are preserved unless explicitly hidden, plus the existence of a hide-replies mode. It omits any note about permissions, reversibility of hiding, or the 300-item cap, but the core behavioral surprise is disclosed.

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?

Three short sentences, zero filler, and the primary action plus its precondition are front-loaded before the secondary hide-replies capability.

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 four-parameter mutation tool with no output schema, the description covers what changes, when to reach for it, and the key side effect on existing replies. It could say whether hiding is reversible and whether repeated calls are safe (idempotentHint=false), which are the remaining 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 description coverage is 100%, so the schema already documents uri, who, account and hide_replies in detail, including the enum values and the 300 max. The description only gestures at the hide-replies capability and adds no syntax or format detail beyond the schema, so the baseline 3 applies.

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 and resource ('change who is allowed to reply to one of your existing posts') plus a second capability ('hide specific replies from the thread'). No sibling tool overlaps this function, so an agent can distinguish it immediately.

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 situational trigger ('the main tool for a post that is going badly') and the precondition that the post is already published, which separates it from create_post/create_thread. It does not name a fallback or state when not to use it, so it stops short of explicit alternatives.

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