Crank Protocol

revoke_session_signer

Idempotent

Instantly revoke a delegated session signer (non-custodial control plane).

Single atomic DB UPDATE -- the gate resolves the row fresh on every call with no cache, so this is enforced on the very next call using signer_pubkey. No TTL/cache window.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "signer_pubkey": "<signer_pubkey>"
    },
    "name": "revoke_session_signer"
  }
}

Input Schema

Name	Required	Description	Default
`caller_id`	No
`signer_pubkey`	Yes

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

First observedJul 27, 2026

TDQS

A4.4/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description goes beyond annotations by detailing the atomic update, the fresh resolution per call, and the lack of cache/TTL window. It transparently indicates that revocation takes effect immediately on the next call, which is a critical behavioral trait. No contradiction with annotations (destructiveHint: false is consistent with a non-destructive state change).

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise, with a clear first sentence stating the core purpose and a second sentence providing technical details. It avoids fluff and is well-structured, making it easy for an agent to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

The description provides sufficient context for the tool's role in the session signer workflow, mentioning non-custodial control plane and the immediate enforcement. It doesn't cover error cases or return values, but since no output schema is provided, that's not a major gap. It also assumes domain knowledge of 'session signer', which is acceptable given the sibling tools list.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description explains that 'signer_pubkey' is used as the identifier, providing meaning for that required parameter. However, it does not mention 'caller_id' at all, leaving its purpose unclear. Since schema coverage is incomplete (only one of two params is addressed), the description adds partial value but not full parameter semantics.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly identifies the action ('revoke a delegated session signer') and the resource ('session signer'). It distinguishes from siblings like authorize or list by focusing on revocation, so an agent can easily understand the tool's purpose.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explains when to use this tool by emphasizing its immediacy ('instantly') and atomicity ('single atomic DB UPDATE'). It doesn't explicitly contrast with alternatives, but the name and context make it obvious that it's for revoking signers, not for listing or authorizing. Minor gap: it doesn't state conditions like 'only for existing signers' or mention that list_session_signers should be used for querying.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

All Crank Protocol tools Inspect

Try in Browser

One endpoint for every MCP toolRayrun runs every MCP server behind one URL and holds the credentials. Each call is decided per client, tool, and argument, then recorded.ray.runAd

Glama MCP Gateway

Add one secure layer between your agents and this server.

Resources

Need Help?