When using this tool, always use the `jq_filter` parameter to reduce the response size and improve performance. Only omit if you're sure you don't need the data. Creates a new signing key pair. When creating a new signing key, the API will generate a 2048-bit RSA key-pair and return the private...
Part of the Mux MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
AI agents use create_system_signing_keys to create or modify resources in Mux. Write operations carry medium risk because an autonomous agent could trigger bulk unintended modifications. Rate limits prevent a single agent session from making hundreds of changes in rapid succession. Argument validation ensures the agent passes expected values.
Without a policy, an AI agent could call create_system_signing_keys repeatedly, creating or modifying resources faster than any human could review. Intercept's rate limiting ensures write operations happen at a controlled pace, and argument validation catches malformed or unexpected inputs before they reach Mux.
Write tools can modify data. A rate limit prevents runaway bulk operations from AI agents.
tools:
create_system_signing_keys:
rules:
- action: allow
rate_limit:
max: 30
window: 60See the full Mux policy for all 98 tools.
Agents calling write-class tools like create_system_signing_keys have been implicated in these attack patterns. Read the full case and prevention policy for each:
Other tools in the Write risk category across the catalogue. The same policy patterns (rate-limit, validate) apply to each.
When using this tool, always use the `jq_filter` parameter to reduce the response size and improve performance. Only omit if you're sure you don't need the data. Creates a new signing key pair. When creating a new signing key, the API will generate a 2048-bit RSA key-pair and return the private key and a generated key-id; the public key will be stored at Mux to validate signed tokens. # Response Schema ```json { $ref: '#/$defs/signing_key_response', $defs: { signing_key_response: { type: 'object', properties: { data: { $ref: '#/$defs/signing_key' } }, required: [ 'data' ] }, signing_key: { type: 'object', properties: { id: { type: 'string', description: 'Unique identifier for the Signing Key.' }, created_at: { type: 'string', description: 'Time at which the object was created. Measured in seconds since the Unix epoch.' }, private_key: { type: 'string', description: 'A Base64 encoded private key that can be used with the RS256 algorithm when creating a [JWT](https://jwt.io/). **Note that this value is only returned once when creating a URL signing key.**' } }, required: [ 'id', 'created_at' ] } } } ```. It is categorised as a Write tool in the Mux MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Add a rule in your Intercept YAML policy under the tools section for create_system_signing_keys. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Mux MCP server.
create_system_signing_keys is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the create_system_signing_keys rule in your Intercept 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 Intercept policy for create_system_signing_keys. 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.
create_system_signing_keys is provided by the Mux MCP server (@mux/mcp). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Open source. One binary. Zero dependencies.
npx -y @policylayer/intercept