One search across every agent registry: 100K+ MCP/A2A/x402 services, signed receipts.
Scored across 5 tools
Each tool covers a distinct stage of the workflow: discovery (search_agents), marketplace-level data (index_stats), per-service evidence (service_evidence), pricing/authorization (quote_call), and execution (call_service). There is no meaningful overlap or ambiguity between tool purposes.
Three tools use a clear verb_noun pattern (call_service, quote_call, search_agents), but index_stats and service_evidence are noun phrases. The names are readable and snake_case is consistent, but the convention is mixed rather than uniform.
Five tools is well-scoped for a service gateway: search, evidence, stats, quote, and call. Each tool has a clear role and no tool feels redundant or unnecessary.
The toolset covers the full agent-facing lifecycle: discovering services, inspecting evidence and index totals, obtaining payment quotes, and executing calls with signed receipts. There are no obvious dead ends or missing operations within the stated domain.
Call a listed remote service THROUGH Clearhouse and get a signed receipt.
Routes the call via the matching protocol adapter (MCP / A2A / HTTP-x402),
enforces spend caps, settles x402 paywalls (dry-run by default), and
returns the result plus a cryptographically signed receipt binding
intent -> execution -> settlement -> outcome.
Args:
listing_id: id from search_agents results
tool: downstream tool name (omit to list the service's tools)
args_json: JSON object of tool arguments
caller_ref: opaque caller identifier for the receipt
payment_json: for paid services — JSON {"authorization": typed_data.message,
"signature": "0x..."} produced by signing quote_call's typed_data with
your own key. Clearhouse relays it; it never sees your private key.
Inputs: listing_id (required), tool, args_json, caller_ref, +1 more. Returns: result
How many listings Clearhouse currently indexes, broken down by source registry.
Inputs: no named parameters. Returns: result
Step 1 of a paid call (non-custodial). Fetches the service's payment requirements and returns the exact EIP-712 typed data your agent must sign with ITS OWN key. Nothing is charged until you sign and pass the result to call_service. If the service is free, says so.
Args:
listing_id: id from search_agents
payer_address: your agent's wallet address (the key that will sign)
args_json: JSON object of query args for the service
Inputs: listing_id (required), payer_address (required), args_json. Returns: result
Search all indexed agent registries at once.
Args:
query: capability keywords, e.g. "pdf extraction", "solana rpc", "payments"
remote_only: only return services callable over the network right now
limit: max results (1-50)
Inputs: query (required), limit, remote_only. Returns: result
Observed facts about a listing: live probe results (handshake, latency, HTTP status) and routed-call history (count, success rate, distinct callers). Includes an arithmetic summary_index with published methodology and a confidence tier. This is EVIDENCE for the caller's own decision — not a safety rating, and Clearhouse never selects or executes on your behalf.
Inputs: listing_id (required). Returns: result
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
Search 15K+ MCP services, A2A agents, and x402 APIs from 5 registries. Paid via x402 (USDC on Base).
Find, trust-check and call 28k+ indexed MCP and A2A agents. Free search; x402 USDC for depth.
AI agent registry — search, discover, register, and connect agents via MCP.
Agent Resource Discovery (ARD, IETF draft) registry: search every ARD registry + verified MCP tools
Add one secure layer between your agents and this server.
