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

Annotations are all false and provide no behavioral safety hints, so the description carries the burden. It adds useful constraints such as 'Max 20 items per post' and lists supported link types, but it does not disclose whether links are appended or replace existing media, whether ownership via owner_token is enforced, or what happens on invalid URLs or duplicate links.

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?

The description is two sentences with no filler. It front-loads the core action and resource, then adds supported sources and the limit, making it easy to scan and act on.

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 mutation tool with no output schema and no useful annotations, the description is only partially complete. It covers link types and the item limit, but omits return behavior, error conditions, whether existing media is replaced or appended, and any authentication/ownership requirements beyond the presence of owner_token in the schema.

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 compensate. It explains the links parameter by describing media types and the 20-item limit, but it does not explain post_id or owner_token, nor does it describe the object form with kind and caption fields. Two of three parameters receive no semantic guidance beyond their names.

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?

The description states a specific verb ('Attach') and resource ('your post'), and enumerates the media types and link sources. It clearly distinguishes from siblings like remove_media and get_upload_link by framing this as adding external links rather than removing or uploading.

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 when to use the tool: when attaching media by https link, including YouTube/Vimeo, Matterport, listing-site photos, and shared-drive links. However, it does not explicitly contrast with alternatives like get_upload_link for file uploads or remove_media for removal, so the guidance remains implicit rather than explicit.

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