mcp-builder
Pass
Audited by Gen Agent Trust Hub on Sep 21, 2026
Risk Level: SAFEINDIRECT_PROMPT_INJECTIONCOMMAND_EXECUTIONEXTERNAL_DOWNLOADS
Full Analysis
- [INDIRECT_PROMPT_INJECTION]: The
evaluation.pyscript implements an automated testing loop that reads questions from an external XML file and passes them directly to an LLM. This creates a surface for indirect prompt injection where malicious questions could attempt to influence the evaluation agent's behavior. - Ingestion points:
scripts/evaluation.pyreads user-provided XML files via theparse_evaluation_filefunction. - Boundary markers: The agent prompt uses XML tags (
<summary>,<feedback>,<response>) to structure the output, but it lacks explicit isolation or instructions to ignore embedded commands within the input questions. - Capability inventory: The script can execute local commands (spawning the MCP server), make network requests to the Anthropic API, and call tools provided by the MCP server.
- Sanitization: No sanitization or validation of the input questions is performed before they are interpolated into the prompt.
- [COMMAND_EXECUTION]: The skill provides a utility for executing and testing MCP servers by spawning them as local subprocesses based on user-supplied command-line arguments.
- Evidence:
scripts/connections.pyusesmcp.client.stdio.stdio_clientto launch servers usingStdioServerParameters, andscripts/evaluation.pyexposes this capability through its-c(command) and-a(args) CLI options. - [EXTERNAL_DOWNLOADS]: The documentation references official Model Context Protocol resources and SDKs hosted on GitHub and the project's documentation site.
- Evidence:
SKILL.mdincludes links tomodelcontextprotocol.ioand themodelcontextprotocolorganization on GitHub for fetching specifications and SDK READMEs.
Audit Metadata