download_from_url

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

With no annotations provided, the description carries full burden. It discloses key behavioral traits: file destination ('samples directory'), return format ('file metadata'), and special capabilities ('custom HTTP headers', 'thug mode for JavaScript execution'). However, it doesn't mention potential side effects like network usage, security implications, or error handling for failed downloads.

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 efficiently structured in two sentences: the first states core functionality and return value, the second adds advanced features. Every phrase adds value with zero redundancy or filler content.

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 6-parameter tool with no annotations and no output schema, the description provides good context about what the tool does and its key features. However, it doesn't fully compensate for the lack of output schema by detailing the metadata structure (hashes, type, size) or addressing potential failure modes.

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 schema fully documents all 6 parameters. The description adds marginal value by mentioning 'custom HTTP headers' and 'optional thug mode', but these are already covered in the schema's parameter descriptions. No additional parameter semantics are provided beyond what's in the structured 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 clearly states the action ('Download a file from a URL'), the destination ('into the samples directory for analysis'), and the return value ('Returns file metadata'). It distinguishes from sibling tools like 'download_file' by specifying URL-based downloading rather than local file operations.

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 provides clear context for usage ('for analysis') and mentions 'thug mode for sites requiring JavaScript execution' as a specific use case. However, it doesn't explicitly state when NOT to use this tool or name alternatives among siblings like 'upload_from_host' for local file operations.

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