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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, and the description adds ordering ('oldest first') and the non-obvious fact that replies sent from native apps also appear as outgoing messages. It does not explicitly describe pagination behavior across pages, which is the main remaining behavioral gap.

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?

Four tight sentences, front-loaded with the core action and return shape, then the id-provenance and downstream-tool notes. Every sentence carries information the agent could not get from the schema alone.

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 no output schema, the description does carry the burden of explaining return contents, and it does so (message history, ordering, associated post fields, per-message ids, outgoing replies). The only omission is how paging interacts with a long conversation history, which the limit/cursor schema only partially implies.

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 100%, so the baseline would be 3, but the description adds provenance for conversation_id (comes from list_inbox_conversations) and clarifies the relationship between message-level inbox ids and the mutation tools. limit and cursor are left entirely to the schema, which is acceptable at full coverage.

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 ('Get the full message history of one inbox conversation') and distinguishes itself from the sibling list_inbox_conversations by scoping to a single conversation. It also names the payload ('with the post it belongs to (caption, link, image)'), so the agent knows what comes back.

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?

Explicitly directs the agent to obtain the argument from list_inbox_conversations and explains that the per-message inbox id is the input for like_inbox_comment, hide_inbox_comment and delete_inbox_comment — effectively a three-way routing instruction. No inference needed about when to call this versus the list or the comment-mutation tools.

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