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

Annotations declare a non-read-only, non-idempotent, closed-world mutation but say nothing about the operation's shape. The description adds genuinely non-obvious behavior: the call yields one shell command per file to execute where the file lives, followed by a separate confirmation, and it imposes a secrecy constraint ('Never show the commands or their links to the person'). It does not disclose command expiry, failure behavior, or repeated-call semantics, so it is not 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?

Three sentences, front-loaded with the supported media shapes, followed by the workflow and then the secrecy rule. No filler, though the critical 'Never show the commands' instruction sits at the very end where it is easiest to miss.

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 carries the burden of explaining what comes back and does so adequately: per-file commands plus a confirmation step. Remaining gaps — what happens on a failed or expired command, whether re-invoking replaces prior preparation, and the maximum of 20 files — are minor but real.

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 id and files fields (name, mime_type, size_bytes, ordering, cover semantics) are already documented. The description restates ordering and cover ('the first one is the cover') and the local-file origin but adds no new syntax or constraints. The phrase 'Name the post' is also slightly misleading, since no name parameter exists in the schema.

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 names a specific action and resource: preparing media files from the local computer for a post on the content calendar, and enumerates the supported shapes (single image, ordered carousel, or video). It does not explicitly name or contrast the sibling it pairs with (confirm-post-media-upload), but the preparation step is clearly distinct from the confirmation step.

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?

It establishes the context of use (adding local media, naming the post, ordering files with the first as cover) and describes the follow-on step ('then you confirm the upload'), which implicitly points the agent at confirm-post-media-upload. There is no explicit statement of when not to use it or how it differs from other content-schedule tools, so it stops short of a 5.

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