Fundraiser API Reference

All fundraiser read APIs are publicly accessible. Contribution recording uses a signed x402 receipt token returned by the fundraiser payment endpoint. Base URL: https://studio.x402layer.cc

List Campaigns

/api/campaigns

Returns all publicly visible campaigns with an agent metadata block.

Query Parameters

Parameter	Type	Description
`limit`	integer	Page size for the campaign list (default `50`, max `200`)
`offset`	integer	Pagination offset (default `0`)
`category`	string	Filter by category (e.g., `tech`, `medical`)
`status`	string	Filter by status (default: shows `active`, `funded`, `launched`, `expired`)

Response

{
  "campaigns": [
    {
      "id": "uuid",
      "slug": "my-campaign-a1b2c3d4",
      "title": "My Campaign",
      "description": "...",
      "images": ["https://..."],
      "target_amount": 10000,
      "raised_amount": 2500,
      "token_ticker": "MYCAM",
      "fee_option": "supporters",
      "status": "active",
      "chain": "solana",
      "deadline": "2026-06-01T23:59:59Z",
      "contributor_count": 12,
      "category": "tech",
      "subcategory": "defi",
      "page_url": "https://studio.x402layer.cc/fundraisers/my-campaign-a1b2c3d4",
      "api_url": "https://studio.x402layer.cc/api/campaigns/my-campaign-a1b2c3d4",
      "created_at": "2026-05-01T12:00:00Z"
    }
  ],
  "pagination": {
    "total": 12,
    "limit": 50,
    "offset": 0,
    "has_more": false
  },
  "agent": {
    "description": "Singularity Fundraisers — crowdfunding campaigns with x402 payments. First 100 supporters earn proportional fee-sharing on the launched token.",
    "protocol": "x402",
    "currency": "USDC",
    "list_url": "https://studio.x402layer.cc/api/campaigns",
    "detail_url_pattern": "https://studio.x402layer.cc/api/campaigns/{slug}",
    "campaign_page_pattern": "https://studio.x402layer.cc/fundraisers/{slug}",
    "supports_pagination": true,
    "supports_category_filter": true,
    "active_count": 3
  }
}

Get Campaign Details

/api/campaigns/{slug}

Returns a single campaign with its contributions and agent metadata including payment instructions.

Response

{
  "campaign": {
    "id": "uuid",
    "slug": "my-campaign-a1b2c3d4",
    "title": "My Campaign",
    "description": "...",
    "images": ["https://..."],
    "target_amount": 10000,
    "raised_amount": 2500,
    "token_ticker": "MYCAM",
    "fee_option": "supporters",
    "fee_split_pct": 0,
    "status": "active",
    "chain": "solana",
    "wallet_address": "ABC...XYZ",
    "deadline": "2026-06-01T23:59:59Z",
    "contributor_count": 12,
    "created_at": "2026-05-01T12:00:00Z"
  },
  "contributions": [
    {
      "wallet_address": "DEF...UVW",
      "display_name": "Alice",
      "amount": 500,
      "chain": "solana",
      "created_at": "2026-05-02T10:00:00Z"
    }
  ],
  "agent": {
    "payment_endpoint": "https://api.x402layer.cc/e/fund-my-campaign-a1b2c3d4",
    "accepts": ["solana"],
    "currency": "USDC",
    "protocol": "x402",
    "min_amount": 1,
    "status": "active",
    "target_amount": 10000,
    "raised_amount": 2500,
    "remaining": 7500,
    "fee_share_eligible": true,
    "fee_share_slots_remaining": 88,
    "campaign_url": "https://studio.x402layer.cc/fundraisers/my-campaign-a1b2c3d4",
    "campaign_api_url": "https://studio.x402layer.cc/api/campaigns/my-campaign-a1b2c3d4",
    "contribute_api": "https://studio.x402layer.cc/api/campaigns/my-campaign-a1b2c3d4/contributions",
    "contribute_api_auth": "none",
    "receipt_header": "X-X402-Receipt-Token",
    "instructions": "To contribute, send a x402 payment to the payment endpoint with an amount query parameter in USDC. After payment, read the X-X402-Receipt-Token response header and POST it to the contribute_api as receipt_token."
  }
}

Agent Metadata Fields

The agent block is designed for AI agents to programmatically discover and interact with campaigns:

Field	Description
`payment_endpoint`	x402-compatible payment URL. Send USDC here.
`fee_share_eligible`	Whether new contributors can still earn fee-sharing
`fee_share_slots_remaining`	How many of the 100 fee-share slots are still open
`remaining`	USDC still needed to reach the target
`contribute_api`	POST endpoint to register the contribution after payment
`receipt_header`	Response header that contains the signed x402 receipt token after a successful payment
`instructions`	Human-readable instructions for making a contribution

Submit a Contribution

/api/campaigns/{slug}/contributions

Record a contribution after a successful x402 payment. The backend verifies a signed receipt token bound to the fundraiser endpoint before accepting the contribution.

Request Body

Field	Type	Required	Description
`receipt_token`	string	Yes	Signed x402 receipt token from the `X-X402-Receipt-Token` response header
`display_name`	string	No	Public name shown in the supporters list (max 50 characters)

Example

# 1. Pay the fundraiser endpoint and capture the X-X402-Receipt-Token header
curl -i "https://api.x402layer.cc/e/fund-my-campaign-a1b2c3d4?action=purchase&amount=100.00"

# 2. Submit the receipt token to record the contribution
curl -X POST https://studio.x402layer.cc/api/campaigns/my-campaign-a1b2c3d4/contributions \
  -H "Content-Type: application/json" \
  -d '{
    "receipt_token": "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...",
    "display_name": "Alice"
  }'

Receipt Verification

The server performs receipt-based verification:

Verifies the receipt JWT signature against x402layer JWKS
Confirms the receipt event is payment.succeeded
Confirms the receipt source_slug matches the specific fundraiser endpoint
Uses the receipt payer_wallet, amount, and tx_hash as the source of truth
Rejects duplicate transaction hashes
Counts contributor slots by unique wallet, not by raw contribution row count

Contributor Count Semantics

contributor_count represents the number of unique contributor wallets for a campaign.

If the same wallet contributes multiple times, it still counts as one contributor.
Fee-share slot eligibility is based on unique wallets, not transaction count.
A wallet’s fee-share weight is based on its total contributed amount across all of its successful contributions.

Response

{
  "success": true,
  "contribution": {
    "id": "uuid",
    "amount": 100,
    "fee_share_eligible": true,
    "new_raised_total": 2600,
    "campaign_status": "active"
  }
}

List Contributions

/api/campaigns/{slug}/contributions

Returns up to 200 contributions for a campaign, ordered by amount (highest first). No authentication required.

Recent Contributions Feed

/api/campaigns/contributions

Returns the 20 most recent contributions across all campaigns. Used for the live ticker display but also useful for monitoring campaign activity.

{
  "contributions": [
    {
      "who": "Alice",
      "amount": 500,
      "campaign": "My Campaign",
      "at": "2026-05-02T10:00:00Z"
    }
  ]
}

Campaign Comments

List Comments

/api/campaigns/{slug}/comments

Returns up to 100 comments on a campaign, ordered by newest first. No authentication required.

Field	Type	Required	Description
`body`	string	Yes	Comment text (1–2,000 characters)
`display_name`	string	No	Public display name (max 50 characters)

Create a Campaign

/api/campaigns

Requires authentication. Creates a new fundraiser campaign.

For agentic creation, you can either use Singularity MCP with a scoped dashboard PAT, or use the direct worker campaign-management surface with an owner-linked X-API-Key. MCP remains PAT-scoped; the direct worker API now accepts existing owner-linked dashboard API keys for campaign management.

Field	Type	Required	Description
`title`	string	Yes	Campaign title (min 3 characters)
`description`	string	No	Campaign description
`wallet_address`	string	Yes	Creator’s Solana wallet for payouts
`target_amount`	number	Yes	Funding target in USDC (minimum $1,000)
`token_ticker`	string	No	2–10 uppercase alphanumeric characters
`fee_option`	string	No	`supporters` (default), `creator`, or `split`
`fee_split_pct`	number	No	Creator’s percentage when using `split` (0–100)
`images`	string[]	No	Array of image URLs (max 5). First image = token logo.
`x_handle`	string	No	X/Twitter handle (without `@`)
`deadline`	string	No	ISO 8601 timestamp. Campaign expires after this date.
`category`	string	No	One of: `medical`, `emergency`, `education`, `community`, `creative`, `tech`, `business`, `personal`, `other`
`bags_config_type`	string	No	Fee tier UUID. See Token Launch.

Response

{
  "success": true,
  "campaign": {
    "id": "uuid",
    "slug": "my-campaign-a1b2c3d4",
    "title": "My Campaign",
    "url": "https://studio.x402layer.cc/fundraisers/my-campaign-a1b2c3d4",
    "endpoint_slug": "fund-my-campaign-a1b2c3d4"
  }
}

Edit a Campaign

/api/campaigns/{slug}

Requires authentication. Only the campaign owner can edit. Editing is blocked once the campaign is funded, launched, or expired.

Editable fields: title, description, x_handle, images, links.

OG Images

Each campaign has an auto-generated Open Graph image available at:

GET /api/og/campaign/{slug}

Returns a 1200x630 PNG image showing the campaign status, title, raised amount, progress bar, and backer count. Used automatically for social media previews when sharing campaign links.

Image Uploads

/api/campaigns/upload

Requires authentication. Upload a campaign image.

Constraint	Value
Max file size	1 MB
Allowed types	JPEG, PNG, WebP, GIF
Validation	Magic byte verification (not just MIME type)

Escrow Wallet

All USDC contributions are held in the platform escrow wallet:

AunvqAg5Zm9yUCPJCeusQwqpF7LhACxmtcmv36PZ47th

This wallet is used for:

Receiving all campaign contributions
Signing token launch transactions
Processing refunds back to contributors

Overview

User Guide

Slayer Agent

Core flows

ERC8004

Skills

Singularity Payments

Agentic Fundraisers

Enterprise

Fundraiser API Reference

Fundraiser API Reference

List Campaigns

Query Parameters

Response

Get Campaign Details

Response

Agent Metadata Fields

Submit a Contribution

Request Body

Example

Receipt Verification

Contributor Count Semantics

Response

List Contributions

Recent Contributions Feed

Campaign Comments

List Comments

Post a Comment

Create a Campaign

Response

Edit a Campaign

OG Images

Image Uploads

Escrow Wallet

Overview

User Guide

Slayer Agent

Core flows

ERC8004

Skills

Singularity Payments

Agentic Fundraisers

Enterprise

Documentation Index

​Fundraiser API Reference

​List Campaigns

​Query Parameters

​Response

​Get Campaign Details

​Response

​Agent Metadata Fields

​Submit a Contribution

​Request Body

​Example

​Receipt Verification

​Contributor Count Semantics

​Response

​List Contributions

​Recent Contributions Feed

​Campaign Comments

​List Comments

​Post a Comment

​Create a Campaign

​Response

​Edit a Campaign

​OG Images

​Image Uploads

​Escrow Wallet

Fundraiser API Reference

List Campaigns

Query Parameters

Response

Get Campaign Details

Response

Agent Metadata Fields

Submit a Contribution

Request Body

Example

Receipt Verification

Contributor Count Semantics

Response

List Contributions

Recent Contributions Feed

Campaign Comments

List Comments

Post a Comment

Create a Campaign

Response

Edit a Campaign

OG Images

Image Uploads

Escrow Wallet