startSignup
Begin an agent-driven sign-up to Stable Baseline. Anonymous-callable. Returns a verification_url and a 6-character user_code that the agent must show to the user. The user opens the URL in their browser, signs in or signs up if necessary, enters the code, and clicks Authorise. The agent meanwhile...
This record as markdown: /tools/io-stablebaseline-sb/startsignup.md
What startSignup does on Stable Baseline
AI agents invoke startSignup to trigger actions in Stable Baseline. 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.
| Parameter | Type | Required | Description |
|---|---|---|---|
intent | string | — | Reason for the signup. Currently only 'mcp_setup' is supported. |
agent_label | string | — | Self-identification of the calling agent (e.g. 'Claude Desktop', 'Cursor', 'Custom CLI'). Shown to the user on the confirmation page so they know what they're a |
desired_org_name | string | — | Optional hint for the org name to suggest if the user has no organisation yet. Ignored for users who already have an org. |
Parameters from the server's own tool schema.
Why startSignup is rated High
startSignup triggers real processes with real consequences. An agent gone sideways doesn't fire it once. It starts dozens of builds, sends mass notifications, or burns through compute before anyone looks up.
Attacks that exploit this kind of access
The rule that runs startSignup safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Stable Baseline, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For startSignup, this is the rule to start with:
startSignup 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 Stable Baseline, apply this rule, and every startSignup call is checked against it from then on.
Questions about startSignup
Begin an agent-driven sign-up to Stable Baseline. Anonymous-callable. Returns a verification_url and a 6-character user_code that the agent must show to the user. The user opens the URL in their browser, signs in or signs up if necessary, enters the code, and clicks Authorise. The agent meanwhile polls pollSignupStatus({device_code}) every poll_interval_seconds until the status changes to authorized, at which point it receives an api_key it can use for subsequent MCP calls. The whole flow has a 10-minute TTL. It is categorised as a Execute tool in the Stable Baseline MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
startSignup accepts 3 parameters: intent, agent_label, desired_org_name. The full parameter table on this page comes from the server's own tool schema.
Register the Stable Baseline MCP server in PolicyLayer and add a rule for startSignup: 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 Stable Baseline. Nothing to install.
startSignup 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 startSignup 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 startSignup. 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.
startSignup is provided by the Stable Baseline MCP server (https://api.stablebaseline.io/functions/v1/cloud-serve/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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