# Airdrop Eligibility Verifier

> Airdrop Eligibility Verifier is a paid API for AI agents from dao.halowerk.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-23).

Analyses caller-supplied evidence signals to classify whether a subject (address, protocol, proposal, etc.) meets airdrop eligibility criteria, returning confidence scores and explicit threshold details.

## Facts

- Endpoint: POST https://dao.halowerk.com/v1/airdrop-eligibility-verifier?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/airdrop-eligibility-verifier-ed2eb9b2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-gNwNT4xkywr0JQ26M2ss

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability airdrop-eligibility-verifier-ed2eb9b2 -d '<json body>'
```

Example prompt: Check airdrop eligibility for address 0xAbC123...def for subject 'MyDAO-Season2-Drop' — I have these signals: failed_criteria=2, snapshot_mismatch=true (observed 2024-11-01T12:00:00Z from on-chain query), and claim_window_gap_days=5 (observed 2024-11-02T09:00:00Z from claim tracker). Use strict mode so missing metrics are flagged explicitly.

## When to prefer this

Choose this endpoint when you need a structured, evidence-based eligibility classification for airdrops using caller-supplied signals rather than live chain queries. It is ideal when you already have extracted eligibility metrics (failed_criteria, snapshot_mismatch, claim_window_gap_days) and need an auditable classification with explicit thresholds and confidence scores. Prefer it over on-chain query tools when you want reproducible, documented assessments that enumerate missing signals rather than silently assuming defaults.

## Known failure modes

- Missing required 'evidence' array or empty array returns 400 validation error
- Strict mode enabled but not all documented metrics supplied — request rejected with list of missing metrics
- Invalid metric enum value in evidence items causes schema validation failure
- Malformed ISO-8601 timestamp on evidence items causes parsing error
- Subject string exceeds 256 character limit returns 400
- More than 50 evidence items supplied exceeds maxItems constraint
- Payment not provided or insufficient — x402 payment required response

## How this service works

Airdrop Eligibility Verifier analyses only the evidence supplied by the caller. It does not claim to query a chain, identify a legal status or replace an independent audit. Missing signals lower confidence and are listed explicitly; every classification includes the exact thresholds used.

## Output

Returns an eligibility classification (eligible/ineligible/uncertain) with an explicit confidence score, the exact threshold values used in the assessment, a list of any missing or low-confidence signals, and the original context labels for correlation.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "strict": {
   "type": "boolean",
   "default": false,
   "description": "Reject unless all documented metrics are supplied."
  },
  "context": {
   "type": "object",
   "description": "Optional non-secret labels returned unchanged for correlation.",
   "maxProperties": 20,
   "additionalProperties": {
    "type": [
     "string",
     "number",
     "boolean",
     "null"
    ]
   }
  },
  "subject": {
   "type": "string",
   "maxLength": 256,
   "minLength": 1,
   "description": "Address, transaction, protocol, asset, proposal or other subject being assessed."
  },
  "evidence": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "metric",
     "value"
    ],
    "properties": {
     "note": {
      "type": "string",
      "maxLength": 500
     },
     "value": {
      "type": [
       "number",
       "boolean"
      ]
     },
     "metric": {
      "enum": [
       "failed_criteria",
       "snapshot_mismatch",
       "claim_window_gap_days"
      ],
      "type": "string"
     },
     "source": {
      "type": "string",
      "maxLength": 300,
      "minLength": 1,
      "description": "Evidence source or query identifier."
     },
     "timestamp": {
      "type": "string",
      "maxLength": 40,
      "minLength": 10,
      "description": "ISO-8601 observation time."
     }
    },
    "additionalProperties": false
   },
   "maxItems": 50,
   "minItems": 1,
   "description": "Caller-supplied observations. Repeated metrics form a time series; the newest timestamp is assessed."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/airdrop-eligibility-verifier-ed2eb9b2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from dao.halowerk.com](https://www.zero.xyz/host/dao.halowerk.com/llms.txt)