verify

Verify a 4QUAYS signed message. No API key required. Returns the verified content plus whether the signature is valid and the signer is active — trust the message only when both hold.

SERVER4quays SOURCE@4quays/mcp

Low RISK CLASS

Category Read

Parameters 30 required

Recommended Allowedsee the rule below

Registry record Grade B, identity unverified Pull the record →

This record as markdown: /tools/4quays-mcp/verify.md

WHAT IT DOES

What verify does on 4quays

AI agents call verify to retrieve information from 4quays without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Parameter	Type	Required	Description
`content`	string	—	The message content (only for a detached v1 signature)
`signature`	string	—	A detached compact JWS signature
`signedMessage`	string	—	A whole 4QUAYS SIGNED MESSAGE block

Parameters from the server's own tool schema.

RISK

Why verify is rated Low

Even though verify only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

Risk signalsAccepts raw HTML/template content (content)

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs verify safely

PolicyLayer is an MCP gateway: it sits between your AI agents and 4quays, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For verify, this is the rule to start with:

verify Allowed

verify is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "verify": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect 4quays, apply this rule, and every verify call is checked against it from then on.

FAQ

Questions about verify

What does the verify tool do? +

Verify a 4QUAYS signed message. No API key required. Returns the verified content plus whether the signature is valid and the signer is active — trust the message only when both hold. It is categorised as a Read tool in the 4quays MCP Server, which means it retrieves data without modifying state.

What parameters does verify accept? +

verify accepts 3 parameters: content, signature, signedMessage. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on verify? +

Register the 4quays MCP server in PolicyLayer and add a rule for verify: 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 4quays. Nothing to install.

What risk level is verify? +

verify is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit verify? +

Yes. Add a rate_limit block to the verify 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.

How do I block verify completely? +

Set action: deny in the PolicyLayer policy for verify. 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.

What MCP server provides verify? +

verify is provided by the 4quays MCP server (@4quays/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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