# TraceFast Address Attributes at Block

> TraceFast Address Attributes at Block is a paid API for AI agents from mpp.tracefast.xyz, paid per call via x402, $0.025/call, status unknown (last checked 2026-10-18).

Returns the attributes an Ethereum address held at the end of a specific block, along with the window each attribute was held for

## Facts

- Endpoint: GET https://mpp.tracefast.xyz/api/v1/chains/1/entities/:address/attributes/at-block?utm_source=zero.xyz
- Price: $0.025/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tracefast-address-attributes-at-block-50ba1533
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UH_geWVmRvl-qvaTwml8m

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 tracefast-address-attributes-at-block-50ba1533
```

Example prompt: What attributes did Ethereum address 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 hold at the end of block 19000000 — I need to see its classification and how long it held each attribute according to TraceFast's knowledge graph.

## When to prefer this

Use this endpoint when you need a point-in-time snapshot of what attributes (classifications, labels, entity types) a specific Ethereum address held at a historical block, including how long each attribute had been held. Prefer this over the current-attributes endpoint when auditing historical state, performing compliance checks at a specific block, or reconstructing how an address was classified during a past event. This is specifically suited for time-anchored knowledge graph queries on Ethereum mainnet (chain 1).

## Known failure modes

- Invalid address format (not 0x-prefixed 40 hex characters) returns an error
- Block number not yet finalized or exceeds chain tip returns an error
- Address has no known attributes in TraceFast knowledge graph at that block returns empty result
- Network or upstream data unavailability returns a service error
- Malformed block parameter (non-numeric or out-of-range) returns a validation error

## How this service works

TraceFast knowledge graph: the attributes an address held at the end of one block, each with the window it held for. Path address: The address, `0x`-prefixed, 40 hex characters, any case. Query block: The block to answer about. Docs: https://docs.tracefast.xyz/api/address-attributes-at-block.md

## Output

A list of attributes associated with the queried Ethereum address as they existed at the end of the specified block, each accompanied by the time window or block range during which the attribute was held. May include entity type classifications, on-chain presence signals, protocol associations, and other knowledge graph labels derived from TraceFast's analytics.

## Request schema (JSON Schema)

```json
{
 "properties": {
  "input": {
   "required": [
    "method"
   ],
   "properties": {
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tracefast-address-attributes-at-block-50ba1533/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mpp.tracefast.xyz](https://www.zero.xyz/host/mpp.tracefast.xyz/llms.txt)