reply

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

Annotations cover the safety profile (write, non-idempotent, non-destructive, open-world), and the description adds genuinely new behavioral context: a quota cost of 50 units and a mandatory preview-then-confirm step before publishing. It omits failure modes and what happens on rejection, which keeps it from a 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?

Two short sentences, front-loaded with the action and actor ('on behalf of the channel'), with the quota cost and confirmation requirement packed into the second. No filler or restatement of the tool name.

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 return values need no explanation, and the description documents the quota cost and confirmation gate, which are the two most consequential facts for calling this tool. The only gap is routing guidance relative to edit_reply, which is a minor omission.

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% with only two parameters (text, thread_id) fully documented in the schema, so the baseline is 3. The description adds no syntax, format or constraint detail for either parameter beyond what the schema already states.

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 (reply/post) and resource (comment thread), plus scoping detail — posted on behalf of the channel — which cannot be inferred from the name alone. Combined with the sibling set, an agent can separate this create-a-reply tool from edit_reply (modify existing) and comment_thread (read).

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 description implies the publish flow (preview then user confirmation) but never states when to pick this over edit_reply or when not to use it, nor does it name any alternative. Usage is only weakly implied by the confirmation sentence, so this is the minimum-viable level.

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