download_instagram_video

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

With no annotations provided, the description carries full burden. It mentions authentication options and file-saving behaviors but lacks critical details: whether authentication bypasses rate limits, what happens if files already exist, error handling, or local filesystem permissions needed. 'Download to local filesystem' implies write operations but doesn't specify risks.

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?

Well-structured with a clear opening sentence followed by Args/Returns sections. Every sentence adds value: the first states purpose, Args explain parameters, Returns specifies output format. Slightly verbose but efficiently organized.

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?

Given 6 parameters, no annotations, and an output schema (which covers return values), the description is moderately complete. It explains parameters well but lacks behavioral context about authentication benefits, file conflicts, or error conditions that would be crucial for a download tool with write operations.

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 provides clear semantic explanations for all 6 parameters: url purpose, optional auth fields, metadata/caption saving behaviors, and download directory override. This adds substantial value beyond the bare schema with only titles.

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 clearly states the specific action ('Download') and target resource ('Instagram video's media files') with destination ('to the local filesystem'). It distinguishes from siblings by specifying 'video' content rather than highlights, posts, profile pictures, or stories.

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 usage for Instagram videos via URLs (posts/reels/tv) but doesn't explicitly state when to use this vs. sibling tools like 'download_instagram_post' which might overlap. It mentions optional authentication but doesn't explain when authentication is needed or beneficial.

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