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Download a direct provider asset file

asset_download_file

Idempotent

Download a file URL returned by Poly Haven, ambientCG, or Smithsonian MCP tools, or a curated Game-icons.net/Kenney direct ZIP, into guarded local storage after license acknowledgement.

Instructions

Download a file URL returned by Poly Haven, ambientCG, or Smithsonian MCP tools, or a curated Game-icons.net/Kenney direct ZIP, into guarded local storage after license acknowledgement. Provider hosts and URL shapes are allowlisted, redirects are revalidated, files are streamed with a byte cap, and existing files are never overwritten.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "provider": "<provider>",
      "url": "<url>",
      "fileName": "<fileName>",
      "acceptLicense": "<acceptLicense>"
    },
    "name": "asset_download_file"
  }
}

Input Schema

Name	Required	Description
`url`	Yes
`fileName`	Yes
`provider`	Yes
`acceptLicense`	Yes	Required acknowledgement that the caller reviewed and accepts the license metadata returned by the provider's search/detail/file tools.

Output Schema

Name	Required	Description	Default
`path`	Yes
`sha256`	Yes
`fileName`	Yes
`provider`	Yes
`sizeBytes`	Yes
`sourceUrl`	Yes
`alreadyExisted`	Yes
`licenseAcknowledged`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

Addedv0.1.1Sep 14, 2026

TDQS

A4.4/5.0

Behavior5/5

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

Annotations show mutability (readOnlyHint=false) and idempotency (idempotentHint=true). Description adds critical details: allowlisted hosts, redirect revalidation, byte cap, and no overwrite policy. No contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences totaling ~70 words, front-loaded with core action and constraints. Every sentence adds value without redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Covers provider scope, license requirement, security measures (allowlist, revalidation, byte cap), and idempotency (no overwrite). Return details are omitted but output schema exists, so complete enough for correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is only 25% (only acceptLicense has description). Description adds context about license acknowledgement and validation of URL shapes, but does not fully explain each parameter's syntax or constraints.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states the tool downloads a file URL from specific providers (Poly Haven, ambientCG, Smithsonian, Game-icons.net/Kenney) with license acknowledgement. Distinct from sibling tools like fab_download_free_asset or audio_download_asset which target different providers.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Implies usage when a file URL from those providers is obtained and license must be accepted. Does not explicitly exclude when not to use or provide alternative sibling tools, but context of siblings is available.

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

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