Create approval links that return decisions to your software.

Fangst creates each approval through an API and connects the result to your own invoice, document, quote, or action. The decision returns through polling or a webhook.

Contact See the API example

From API call to structured result.

Create the approvalSoftware or an AI agent supplies the exact subject and available decisions.
Share the URLThe approver sees what needs a decision and approves or rejects it.
Read the decisionFangst returns the recorded decision through the API or a signed webhook.

Use a decision API instead of form-response logic.

Your system creates the approval and receives a result that already contains the subject id, version, decision, and timestamp.

Create

POST https://api.fang.st/v1/approvals
Authorization: Bearer <FANGST_API_TOKEN>
Content-Type: application/json

{
  "title": "Approve proposal",
  "subject": {
    "type": "proposal",
    "id": "prop_77",
    "version": 4
  },
  "decisions": [
    "approve",
    "reject"
  ]
}

Completed result

{
  "status": "decided",
  "decision": "approved",
  "decided_at": "2026-09-14T12:30:00Z"
}

Use REST, MCP, polling, or webhooks.

Software uses the HTTP resources directly. Authorized AI agents can use the same API or intention-oriented Fangst MCP tools.

POST/v1/approvalsCreate an approval and receive its hosted URL.

GET/v1/approvals/:idRead the decision and its receipt.

POST/v1/approvals/:id/disableClose an approval link.

MCPrequest_human_approvalLet an authorized agent request a decision.

MCPget_human_approvalLet the agent read the decision.

Fangst runs the hosted interaction.

Hosted page

Responsive pages, clear sender context, validation, private or shared links, expiry, and submission limits.

Structured result

Typed values, authenticated file downloads, correlation metadata, timestamps, and stable response ids.

Reliable delivery

Polling, signed webhooks, retries with backoff, delivery history, idempotency, and replay.

Pay for completed interactions. No subscription.

Start with $1 free. Add funds from $10. Links, polling, webhooks, and abandoned requests do not use the main billable unit.

See pricing

Give your software a way to ask people.

Create the hosted interaction through Fangst and receive the structured result back.

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