# SignalLayer

Machine-native decision and data primitives. Free deterministic routing, then pay per call with x402 V2. No API key or subscription.

## Start here

signal_layer_router — FREE
Use when an agent knows its task but is not certain which SignalLayer primitive matches it.
Returns no_match or one recommendation with current price, routing confidence, missing inputs, and ready-to-call HTTP/MCP arguments.
HTTP: GET/POST /_api/v1/router
MCP: signal_layer_router

## Paid primitives

agent_preflight — $0.01 USDC
Use before paying, transferring to, or interacting with an unfamiliar machine resource, x402 endpoint, recipient, or Base address.
HTTP: GET/POST /_api/v1/agent/preflight
MCP: agent_preflight

market_execution_intel — $0.03 USDC
Use before an exact-in ERC-20 swap on Base when live execution conditions matter.
HTTP: GET/POST /_api/v1/market/execution-intel
MCP: market_execution_intel

structured_extract — $0.02 USDC
Use when facts exist on a public webpage but compact structured JSON is required.
HTTP: GET/POST /_api/v1/web/structured-extract
MCP: structured_extract

## Discovery

GET /_api/tools
GET /_api/openapi
GET /_api/llms
GET /_api/skill
MCP /_api/mcp

## Payment

x402 V2 exact payment on Base mainnet (eip155:8453), USDC.
Unpaid HTTP requests return 402 with PAYMENT-REQUIRED.