Get a list of all source libraries (RISM sigla) in the archive with record counts and location info
AI agents call list_sources to retrieve information from Digital Guitar Archive MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves and lists informational metadata about source libraries (RISM sigla, record counts, location info) from a database. It performs a query operation with no ability to modify, delete, or execute arbitrary actions. The blast radius is minimal—misuse by an AI agent would only result in enumeration of available sources, with no data modification or external side effects possible.
From the tool's definition Tool name 'list_sources' and description 'Get a list of all source libraries' indicates retrieval of metadata without modification. Server description emphasizes 'search and retrieve records' with 'no side effects' consistent with Read operations.
Attacks that exploit this kind of access
Get a list of all source libraries (RISM sigla) in the archive with record counts and location info. It is categorised as a Read tool in the Digital Guitar Archive MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Digital Guitar Archive MCP Server MCP server in PolicyLayer and add a rule for list_sources: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Digital Guitar Archive MCP Server. Nothing to install.
list_sources is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the list_sources rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for list_sources. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
list_sources is provided by the Digital Guitar Archive MCP Server MCP server (rcoldwell/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
list_sources is one line of Digital Guitar Archive MCP Server's registry record.
The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.
Teams ship this data inside their own products. See what a licence covers →