start_tool_session
Create a short-lived allowlist for discover_tools and run_tool. Use this to keep a task scoped to the tools it actually needs.
This record as markdown: /tools/heznpc-airmcp/start-tool-session.md
What start_tool_session does on AirMCP
AI agents invoke start_tool_session to trigger actions in AirMCP. 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 start_tool_session is rated High
This tool configures execution permissions and scope for downstream tool operations. While it does not directly perform an action on user data, it sets up the execution environment and allowlist for other tools to run—making it an Execute category risk. It is not Destructive (no deletion), not Financial (no money movement), not Write (no direct data modification).
From the tool's definition Tool description states it "Create[s] a short-lived allowlist for discover_tools and run_tool," indicating it enables and controls execution of other tools by establishing scope and permissions for tool discovery and execution.
Attacks that exploit this kind of access
The rule that runs start_tool_session safely
PolicyLayer is an MCP gateway: it sits between your AI agents and AirMCP, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For start_tool_session, this is the rule to start with:
start_tool_session 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 AirMCP, apply this rule, and every start_tool_session call is checked against it from then on.
Questions about start_tool_session
Create a short-lived allowlist for discover_tools and run_tool. Use this to keep a task scoped to the tools it actually needs. It is categorised as a Execute tool in the AirMCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Air MCP server in PolicyLayer and add a rule for start_tool_session: 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 AirMCP. Nothing to install.
start_tool_session 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 start_tool_session 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 start_tool_session. 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.
start_tool_session is provided by the Air MCP server (airmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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