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Squatch MCP

MCP Endpoint Lint - handshake, tool schemas, JSON-RPC errors

dev.workers.pathwren.www/mcp-endpoint-lint

by dev.workers.pathwren.www· v1.3.0Source: Official MCP Registry

Findings

Detected by Squatch rules from the server's metadata and protocol behavior. Latest completed scan: .

Severity: High4 findings

Severity: HighStatus: OpenSQ-RESOURCE-SENSITIVE-URI

Resource at a sensitive system or credential path

A resource or resource template points at a sensitive system, key or credential location.

First seen · Last seen

Suggested fix: Do not expose credential or system configuration paths as resources.

Severity: HighStatus: OpenSQ-RESOURCE-INJECTION

Resource metadata contains directives to the AI model

A resource's metadata contains instructions addressed to the AI model.

First seen · Last seen

Suggested fix: Describe resources neutrally.

Severity: HighStatus: OpenSQ-TOOL-SENSITIVE-PATH-REFERENCE

References credential or key locations

Model-facing text references credential, key or configuration file locations unrelated to the tool's stated purpose.

First seen · Last seen

Suggested fix: Remove references to credential files, key stores and client configuration files.

Severity: HighStatus: OpenSQ-TOOL-INJECTION-INSTRUCTIONS

Instructions addressed to the AI model

Model-facing text contains instructions addressed to the AI model rather than a description of the tool (for example to override prior instructions, to act before using tools, or to react to trigger phrases).

First seen · Last seen

Suggested fix: Describe what the tool does and its parameters. Do not include instructions to the model about other tools, the user or the conversation.

Severity: Medium5 findings

Severity: MediumStatus: OpenSQ-SERVER-AUTH-NONE-WRITE

State-changing tools available without authentication

The remote server lists state-changing tools without requiring authentication.

First seen · Last seen

Suggested fix: Require MCP authorization for servers that expose state-changing tools.

Severity: MediumStatus: OpenSQ-PROMPT-INJECTION

Prompt metadata contains directives to the AI model

A prompt's description or arguments contain instructions addressed to the AI model.

First seen · Last seen

Suggested fix: Describe prompts neutrally.

Severity: MediumStatus: OpenSQ-TOOL-INJECTION-INSTRUCTIONS

Instructions addressed to the AI model

Model-facing text contains instructions addressed to the AI model rather than a description of the tool (for example to override prior instructions, to act before using tools, or to react to trigger phrases).

First seen · Last seen

Suggested fix: Describe what the tool does and its parameters. Do not include instructions to the model about other tools, the user or the conversation.

Severity: MediumStatus: OpenSQ-TOOL-INJECTION-INSTRUCTIONS

Instructions addressed to the AI model

Model-facing text contains instructions addressed to the AI model rather than a description of the tool (for example to override prior instructions, to act before using tools, or to react to trigger phrases).

First seen · Last seen

Suggested fix: Describe what the tool does and its parameters. Do not include instructions to the model about other tools, the user or the conversation.

Severity: MediumStatus: OpenSQ-TOOL-INJECTION-INSTRUCTIONS

Instructions addressed to the AI model

Model-facing text contains instructions addressed to the AI model rather than a description of the tool (for example to override prior instructions, to act before using tools, or to react to trigger phrases).

First seen · Last seen

Suggested fix: Describe what the tool does and its parameters. Do not include instructions to the model about other tools, the user or the conversation.

Severity: Low2 findings

Severity: LowStatus: OpenSQ-CONFORMANCE-MODERN-FAILURE

Protocol conformance checks failed

The server failed one or more MCP protocol conformance checks.

First seen · Last seen

Suggested fix: Review the failed checks against the MCP specification.

Severity: LowStatus: OpenSQ-REPO-MISSING

No source repository linked

No source repository is linked in the registry entry.

First seen · Last seen

Suggested fix: Add a repository to server.json.

What this scan does not cover

  • Squatch never calls a server's tools, so it cannot see what they actually do at run time.
  • It scans without credentials: tools behind authentication may not be visible.
  • It does not review source code, dependencies or the publisher's infrastructure.
  • A server can change behavior between scans; monitoring compares each scan with the last.
  • Classifications come from tool names, descriptions and schemas, which the publisher controls.

How Squatch scans servers