api_call
Make a direct API call to any connected service. For advanced use when you need fine-grained control beyond the execute tool.
This record as markdown: /tools/io-github-0nork-0nmcp/api-call.md
What api_call does on 0nmcp
AI agents invoke api_call to trigger actions in 0nmcp. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call: builds kicked off, notifications sent, workflows started.
Why api_call is rated High
This tool can invoke arbitrary APIs on connected services with user-supplied parameters. While the name alone is neutral, the description 'direct API call' and 'fine-grained control' indicate the ability to trigger external operations whose side effects depend entirely on the API endpoint and arguments provided. This matches Execute category (triggers external operations whose effects depend on arguments).
From the tool's definition Tool enables 'direct API call to any connected service' with 'fine-grained control', allowing arbitrary requests to external APIs whose effects are determined by arguments and target service implementation.
Attacks that exploit this kind of access
The rule that runs api_call safely
PolicyLayer is an MCP gateway: it sits between your AI agents and 0nmcp, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For api_call, this is the rule to start with:
api_call stays usable, but rate-capped: a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect 0nmcp, apply this rule, and every api_call call is checked against it from then on.
Questions about api_call
Make a direct API call to any connected service. For advanced use when you need fine-grained control beyond the execute tool. It is categorised as a Execute tool in the 0nmcp MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the 0n MCP server in PolicyLayer and add a rule for api_call: 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 0nmcp. Nothing to install.
api_call is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the api_call 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 api_call. 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.
api_call is provided by the 0n MCP server (0nmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
More on 0n, and thousands of servers like it.
This server
Across the catalogue