Bluepages

800K+ verified Ethereum address <> Twitter/X mappings, plus Farcaster.

Setup

Requires the Bluepages MCP server: npx -y github:bluepagesdoteth/bluepages-mcp or direct API calls (see below). The MCP server is the recommended way to use Bluepages.

Authentication

Requires one of these env vars:

BLUEPAGES_API_KEY (recommended) — 20% cheaper, 2x rate limits.
PRIVATE_KEY — Ethereum private key for x402 pay-per-request (USDC on Base).

Security note: Never use a main wallet key. Use a dedicated, funded-only-as-needed agent wallet if providing PRIVATE_KEY.

With a private key, you can either pay per request via x402 or purchase a BLUEPAGES_API_KEY using the get_api_key and purchase_credits MCP tools.

Without a private key, the user must get an API key at bluepages.fyi/api-keys and set BLUEPAGES_API_KEY.

Tools (quick reference)

| Tool | Cost | Description | | -------------------------- | ---------------------- | -------------------------------------------------- | | check_address | 1 credit ($0.001) | Check if address has data | | check_twitter | 1 credit ($0.001) | Check if Twitter handle has data | | get_data_for_address | 50 credits ($0.05) | Full identity data for address (free if not found) | | get_data_for_twitter | 50 credits ($0.05) | Full identity data for handle (free if not found) | | batch_check | 40 credits ($0.04) | Check up to 50 items at once | | batch_get_data | 40 credits/found item | Data for up to 50 items (x402: $2.00 flat/batch) | | batch_check_streaming | same as batch_check | For large lists (100+), shows progress | | batch_get_data_streaming | same as batch_get_data | For large lists (100+), shows progress | | check_credits | free | Check remaining credits (API key only) | | set_credit_alert | free | Set low-credit warning threshold (API key only) | | get_api_key | free | Get/create API key via wallet signature | | purchase_credits | $5–$600 USDC | Buy credits via x402 (PRIVATE_KEY only) |

Input format

Addresses: 0x-prefixed, 42-char hex. Case-insensitive.
Twitter handles: With or without @.

Cost-saving workflow

Single lookups: check_address/check_twitter first (1 credit), then get_data_* only if found (50 credits). Skipping the check wastes credits on misses.
Batch lookups: Always two-phase — batch_check then batch_get_data on found items only. This saves ~90% vs fetching everything blind.
Large lists (100+): Use _streaming variants for progress updates.

Rate limits

API Key: 60 req/min
x402: 30 req/min
Batch: max 50 items per request

Alternative: Direct HTTP API

If MCP is unavailable, call the API directly. Auth depends on your setup:

API key: pass X-API-KEY header
Private key (x402): endpoints return a 402 with payment details; sign and resend with X-PAYMENT header

# With API key
curl "https://bluepages.fyi/check?address=0x..." -H "X-API-KEY: your-key"
curl "https://bluepages.fyi/data?address=0x..." -H "X-API-KEY: your-key"

# Batch check
curl -X POST "https://bluepages.fyi/batch/check" \
  -H "X-API-KEY: your-key" -H "Content-Type: application/json" \
  -d '{"addresses": ["0x...", "0x..."]}'

Full API docs: bluepages.fyi/docs