send_file

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

With no annotations, the description carries the full load and does meaningful work: the path is resolved on the bridge host (not the caller's machine), only photo/video are accepted, view_mode produces disappearing media, and videos must be H.264 mp4. It omits failure modes, size limits, and permission requirements, but the host-resolution disclosure is exactly the kind of context annotations would otherwise have to supply.

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?

Front-loads the what and the hard constraint in one sentence, then presents parameters as a compact Args block. Only mild redundancy between the host-path sentence and file_path's parenthetical.

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 not be explained. For a mutation tool with zero annotation coverage and zero schema descriptions, the description supplies the file-type restriction, host path semantics, and view_mode behavior, leaving only edge cases uncovered.

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, and it documents all three params: file_path (resolved on the bridge host), to (chat alias with omit-to-default behavior), and view_mode (once vs replayable with format implications). Only missing details like path format or alias resolution rules keep this from a 5.

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 ('Send a photo or video') and immediately narrows the resource with an Instagram DM constraint. It plausibly separates itself from send_audio (audio-only), though the boundary with the sibling share_media is not addressed.

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 real conditional guidance for two params ('Omit for the sole subscribed target', 'Omit for a normal one'), which implies usage. However, it never says when to prefer this over send_audio or share_media, so alternative selection is left to inference.

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