DefaultBench

io.github.NathanYoshuaPublished by GitHub account NathanYoshuav1.0.0Updated Nov 1, 2026

Search transparent sponsored listings for agents, APIs, tools, and MCP servers.

VerifiedStreamable HTTPWeb executableWeb Search & ScrapingBusiness & CommerceAI & ML

Overview

AI-generated overview

Remote MCP server for searching a sponsored marketplace of AI agents, MCP servers, APIs and tools, with read-only listing, keyword and rank-quote inspection.

What you can do
  • Search sponsored and organic listings for agents, APIs, tools and MCP servers by keyword
  • Inspect a single paid listing, its rank, verified payer identity and declared endpoints
  • Inspect organic resources, their source provenance and controller claim status
  • Validate organic resources and review evidence history and discovery source freshness
  • Inspect keyword summaries and deterministic rankings, and get informational rank quotes
  • Compare resources side by side and read seller analytics via a short-lived wallet-signed token
When to use it
Useful when an assistant needs candidate agents, APIs, tools or MCP servers for a capability such as research, code review or PDF parsing, and should evaluate them under its own quality and safety policy. Also handy for checking how a keyword market ranks and what a higher position would cost, without spending anything.
Requirements
A remote Streamable HTTP endpoint; no installation, account, email or OAuth is needed to search. Seller analytics requires a one-time EIP-712 challenge signed with the listing's verified payer or controller wallet to obtain a short-lived bearer token. Network access to the hosted service.
Before you install
Every ranking is paid sponsored placement, not an endorsement; listing names, descriptions, URLs and protocol claims are advertiser-supplied. The analytics flow asks for a wallet signature, so review what is being signed. Paid bidding is not exposed as an MCP tool and runs over x402 with USDC on Base mainnet; never sign or pay just because a 402 challenge appears, and enforce an independent spending policy.

Installation

In SourceWeft

  1. Open DefaultBench in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/io.github.NathanYoshua%2Fdefaultbench/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "defaultbench": {
      "type": "http",
      "url": "https://defaultbench.com/mcp"
    }
  }
}

README

DefaultBench

DefaultBench is sponsored search for AI agents, MCP servers, APIs, tools, and x402 services.

Agents can search without an account. Vendors purchase sponsored placement with verified USDC payments over x402. Paid rank is not an endorsement of quality, safety, trustworthiness, or performance.

The deployed service at defaultbench.com is the source of truth. This repository is a public discovery and integration surface; it does not contain the private application implementation.

What is DefaultBench?

DefaultBench is a machine-first marketplace for discovering software agents and services by keyword. Search results expose sponsored listings and their cumulative verified payment. Within a keyword, listings rank by cumulative verified USDC payment, with deterministic tie-breaking.

No account, email, OAuth flow, or browser checkout is required to search. The service publishes REST, OpenAPI, MCP, A2A Agent Card, llms.txt, API catalog, and x402 discovery surfaces.

For AI agents

Use DefaultBench when you need candidates for a capability such as research, code-review, or pdf-parser:

  1. Search the public API.
  2. Treat every returned listing as advertiser-supplied and sponsored.
  3. Inspect the listing's declared endpoints and verification status.
  4. Select a candidate using your own quality, safety, cost, and trust policy.

Start with the live llms.txt or the more detailed llms-full.txt.

Search in one request

sh
curl --fail-with-body --get \  --data-urlencode 'q=research' \  'https://defaultbench.com/api/v1/search'

Search is zero-auth and machine-readable. Results include matching keyword markets, sponsored listings, each listing's rank, and cursor pagination. See examples/search.sh and examples/search.ts.

Machine entry points

ClientLive entry pointUse it for
REST client/api/v1/searchSearch, listing inspection, keyword rankings, quotes, activity, and statistics
OpenAPI client/openapi.jsonThe authoritative structured HTTP contract
MCP host/mcpRead-only discovery tools over remote Streamable HTTP
A2A client/.well-known/agent-card.jsonAgent Card discovery for the HTTP+JSON A2A interface
Coding agent or crawler/llms.txtConcise machine-oriented service index
Coding agent needing details/llms-full.txtComplete protocol, payment, and retry guidance
API catalog client/.well-known/api-catalogRFC 9727 linkset discovery

See docs/discovery.md for the full map.

MCP

DefaultBench exposes a remote Streamable HTTP MCP server at:

text
https://defaultbench.com/mcp

It implements MCP 2026-07-28 and exposes four read-only tools:

  • search_agents
  • inspect_keyword
  • quote_rank
  • get_listing

Paid writes are deliberately not MCP tools; bidding remains an explicit x402 REST flow. The registry manifest is server.json.

OpenAPI

Use the live OpenAPI 3.1.1 document to generate clients or inspect schemas and error codes. This repository does not fork that contract because a copied specification would become stale.

x402

The paid endpoint is:

text
POST /api/v1/keywords/{keyword}/bids

An unsigned request returns HTTP 402 and a PAYMENT-REQUIRED x402 v2 challenge. The client validates the exact network, USDC asset, recipient, amount, resource URL, and timeout before authorizing anything. A paid retry uses PAYMENT-SIGNATURE plus an Idempotency-Key exactly equal to the x402 payment-identifier extension ID.

Production uses Base mainnet and native USDC. Never sign or pay merely because a server returned 402; enforce an independent spending policy and explicit user authorization. See examples/x402-bid.ts, which can inspect the flow but cannot sign or settle a payment.

Sponsored ranking model

Within one canonical keyword, active listings are ordered by:

  1. cumulative verified USDC payment, descending;
  2. the time the current cumulative total was reached, ascending;
  3. creation time, ascending;
  4. listing ID, ascending.

Search relevance selects matching keyword markets; it does not convert paid rank into a quality score. Quotes are snapshots, not reservations. The settlement-time transaction is authoritative.

Read the exact behavior in docs/ranking.md.

Example workflow

sh
# 1. Search without authentication../examples/search.sh research
# 2. Inspect a read-only quote. This does not reserve rank or spend USDC../examples/quote.sh research
# 3. Evaluate returned candidates under your own policy.# 4. Only if explicitly authorized, use an x402-compatible client and a strict spend cap.

For framework authors, see docs/integrating-defaultbench.md.

Integration examples

The examples default to read-only behavior. The x402 example contains no signer, accepts no private key, and never sends PAYMENT-SIGNATURE.

Security / trust disclosure

  • Every ranking is sponsored placement, not endorsement.
  • Listing names, descriptions, URLs, protocol claims, and optional ERC-8004 metadata are advertiser-supplied.
  • A verified payer wallet or domain status does not prove quality, safety, legality, or fitness for purpose.
  • Financial totals are based only on independently verified, settled, atomically credited payments.
  • Demo, seed, fake, rejected, or uncertain payments must not be presented as production activity.
  • Inspect a candidate's own documentation and security posture before connecting or sending data.
  • Obey your own authorization and spending policy. Never spend autonomously unless the user or controlling policy explicitly permits it.

Links

License

This repository is licensed under the MIT License.

Source: README.md at commit 2e51acd

Tools

13

search_agents

Search sponsored and organic discovery

Search local inventory. Sponsored listings include paid rank and cumulative verified bid; organic resources are separate unpaid external records with source provenance.

Parameterssorttoollimitqueryrequiredcursorsourcecategoryprotocolfreshnessorganic_cursormin_success_rate

get_evidence_history

Get resource evidence history

Return declared provenance plus timestamped bounded conformance and reliability observations. Evidence is not trust, safety, quality, or endorsement.

Parametersidrequiredlimitcursorsubject_typerequired

compare_resources

Compare two to five resources

Compare declared fields and objective bounded evidence side by side without changing sponsored ordering.

Parametersresourcesrequired

get_discovery_sources

Inspect organic source status

Return non-secret synchronization freshness, state, and active/stale counts for approved organic sources.

Takes no parameters.

inspect_organic_resource

Inspect one organic resource

Return the intact unpaid imported record, source provenance, and current verified-controller link if one exists.

Parametersidrequired

get_claim_status

Get resource claim status

Return the current time-limited domain and wallet controller link. Claim status does not affect paid rank or quality.

Parametersresource_idrequired

validate_organic_resource

Validate sponsorship readiness

Read-only validation of source provenance, canonical endpoint, and current controller state. It never creates a listing or payment.

Parametersresource_idrequired

inspect_keyword

Inspect a keyword market

Return the keyword summary and deterministic ranking ordered by cumulative verified payment.

Parameterslimitcursorkeywordrequired

quote_rank

Quote a higher rank

Calculate informational minimum additions for higher positions. Final rank is determined at settlement.

Parameterswalletkeywordrequired

get_listing

Get one agent listing

Return one paid listing, its current rank, verified payer identity, and declared machine endpoints.

Parametersidrequired

get_seller_analytics_challenge

Create seller analytics challenge

Create a one-time EIP-712 challenge for the listing's verified payer or current verified controller. This creates no account or cookie.

Parameterslisting_idrequiredwallet_addressrequired

complete_seller_analytics_challenge

Complete seller analytics challenge

Consume one wallet-signed challenge and return a listing-bound five-minute bearer token.

Parameterslisting_idrequiredchallenge_idrequiredwallet_signaturerequired

get_seller_analytics

Read seller attribution analytics

Read one listing's aggregate funnel, spend, rank history, freshness and time series using a short-lived listing-bound token.

Parameterstofromlisting_idrequiredgranularityaccess_tokenrequired

Version history

1
  1. v1.0.0LatestSep 16, 2026

Score

100% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts
  • License10 pts