# ChEMBL Affinity Oracle MCP

> ChEMBL Affinity Oracle MCP is a paid API for AI agents from api.m2mcent.com, paid per call via x402, $0.3/call, status unknown (last checked 2026-09-14).

Queries and predicts compound-target binding affinity data using the ChEMBL bioactivity database

## Facts

- Endpoint: POST https://api.m2mcent.com/chembl-affinity-oracle-mcp/api/process
- Price: $0.3/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/chembl-affinity-oracle-mcp-bccb3e23
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_EkX6Cm6V90sMGN7jSs3YE

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 chembl-affinity-oracle-mcp-bccb3e23 -d '<json body>'
```

Example prompt: Can you look up the binding affinity and IC50 values for imatinib against the BCR-ABL kinase target using the ChEMBL affinity oracle?

## When to prefer this

Choose this endpoint when you need structured, curated bioactivity and binding affinity data sourced from the ChEMBL database for drug discovery or cheminformatics workflows. Prefer it over generic chemistry search APIs when you specifically need quantitative pharmacological activity data (IC50, Ki, EC50) against named protein targets.

## Known failure modes

- Compound or target not found in ChEMBL database returns empty or null results
- Ambiguous query string leads to multiple matched entries requiring disambiguation
- Malformed SMILES or invalid ChEMBL ID returns a parsing error
- Network timeout or service unavailability returns a 402 or 5xx error
- Query too broad returns truncated or paginated results

## How this service works

The premier global index of 1,069 monetized MCP nodes across 205 specialized subdomains. Gasless USDC runtime settlements via x402 V2 Spec on Base L2. Save 95% token context.

## Output

Returns bioactivity and binding affinity data from ChEMBL, including quantitative measures such as IC50, Ki, EC50, or Kd values for the queried compound-target pair, along with assay metadata and confidence information.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "payload": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/chembl-affinity-oracle-mcp-bccb3e23/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.m2mcent.com](https://www.zero.xyz/host/api.m2mcent.com/llms.txt)