Read the complete contents of a file as text. DEPRECATED: Use read_text_file instead.
AI agents call read_file to retrieve information from Server Sequential Thinking without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves file contents without modification, creation, or deletion. It is a straightforward data retrieval operation. The deprecation notice does not change its fundamental behavior. The low severity reflects minimal blast radius—an AI agent misusing this tool would only access existing data it may not be authorized to see, not modify or destroy anything.
From the tool's definition Tool name is 'read_file' and description states 'Read the complete contents of a file as text.' This is a pure read operation with no side effects.
Attacks that exploit this kind of access
Read the complete contents of a file as text. DEPRECATED: Use read_text_file instead. It is categorised as a Read tool in the Server Sequential Thinking MCP Server, which means it retrieves data without modifying state.
Register the Server Sequential Thinking MCP server in PolicyLayer and add a rule for read_file: 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 Server Sequential Thinking. Nothing to install.
read_file 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 read_file 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 read_file. 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.
read_file is provided by the Server Sequential Thinking MCP server (@modelcontextprotocol/server-sequential-thinking). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
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