Open-source B2B and marketplace ecommerce; new stores include an MCP server for AI agents.
Sourcey
Overview
Description from the maker (original English)
Find startup credits and deals; check eligibility and read Agent Readiness reports with evidence.
PopNx MCP’s three pillars
These three are never merged into one score: opinions, measurements and popularity are different things.
- User voiceiNo reviews yetReviews open together with accounts in a later step
- Our basic checksi3 of 3 passedChecked from public information; code not scanned yet
- UsageiNot measured yet★ –
What you can do with it
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
- Connection: Runs in the cloud
- Transport: Streamable HTTP
- Category: Online shops & payments
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 3 of 3 passed
- Runs on the maker’s server: what you ask it goes through their server.
- Can do 9 things (tools) search_offers, compare_offers, inspect_evidence, get_changes …
- The registry lists no key to fill in.
You need
- Runs in the cloudNothing to install; it connects over the internet
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
Works in Claude on the web, desktop and mobile:
- Open Settings → Connectors
- Press Add custom connector
- Paste the address below and press Add
- If it asks you to sign in, sign in with the maker
https://mcp.sourcey.com/mcpRun this in your terminal
claude mcp add --transport http sourcey https://mcp.sourcey.com/mcpOr copy the settings yourself
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"sourcey": {
"url": "https://mcp.sourcey.com/mcp"
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Or copy the settings yourself
Paste into .vscode/mcp.json in your project
{
"servers": {
"sourcey": {
"type": "http",
"url": "https://mcp.sourcey.com/mcp"
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
ChatGPT connects only to servers on the internet:
- Open ChatGPT on the web → Settings → Connectors (Apps)
- Press Create or Add (some plans need Developer mode under Advanced first)
- Paste the address below, give it a name and save
- If it asks you to sign in, sign in with the maker
https://mcp.sourcey.com/mcpMenu names can differ slightly by plan and over time.
Your choice stays on this device in a cookie; no account needed.
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
What it can do
Tool names and descriptions exactly as the server reported them on Nov 6, 2026. The maker wrote them, not us; we show them as plain text.
search_offersSearch current startup credits and deals, including cloud credits, SaaS discounts, free tiers, grants, perks, and partner offers. Filter by query, vendor, or category and evaluate eligibility from typed company facts; unknowns remain explicit.
compare_offersCompare two to ten startup credit or deal offers side by side, including value, access requirements, eligibility, freshness, and evidence. Unknown eligibility and unsupported stacking remain explicit.
inspect_evidenceInspect the provenance behind startup credits and deals. Resolve one to ten exact revisions to supporting events and observations, including freshness and dispute status.
get_changesTrack added, changed, withdrawn, and removed startup credits, discounts, free tiers, perks, and deals through Sourcey's signed change feed after an optional cursor.
search_readinessSearch published Agent Readiness report cards. Each card grades one named job on a vendor's service by where a person or the vendor has to step in on an agent's path to it, from its listing and from probes that send the job's request with no account (or, where its interface has n
get_readinessGet one published Agent Readiness report card: the job and the interface whose path it grades (none for an F card whose listing names no interface), the letter and its statement, each step's outcome, approvals and human workarounds, the evidence label (probed, or the job verified
get_reportGet the State of Startup Credits or the State of Agent Readiness report: the figures of one Catalog release (offers by size, by how a startup reaches them and by their terms; report cards by grade, by step and by category), that release's names for every company, offer and report
prepare_declarationPrepare the canonical Agent Readiness declaration for one service and job: participants, endpoints, API and MCP interfaces, the job operation on each interface that performs the job (the request the probes send with no account, or the operation in the vendor's OpenAPI document wh
get_servicesDiscover Sourcey's enabled paid agent services and canonical HTTP resources, including exact request and response contracts, price floor, policy links, and x402 discovery. Payment and durable job status remain on the product HTTP API; this read-only MCP tool never signs, settles,
Basic checksi
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified against the domain sourcey.com (the registry checks domain ownership)
- … Not checked yet
Still maintained
We have not read this repo from GitHub yet
- … Not checked yet
Has a licence
We have not read this repo from GitHub yet
- ✓ Pass
Endpoint responds
Responded in 124 ms (HTTP 200)
- – Not applicable
Sign-in with OAuth
No sign-in needed
- ✓ Pass
No hidden instructions in tool descriptions
Read 9 tool descriptions and found no hidden instructions to the AI
Compared with others in Online shops & paymentsi
- More stars than 0% of the other 2534 servers in this category
- Published to the registry more recently than 86% of the other 2534 servers in this category
- Basic checks equal to or better than 100% of the other 2534 servers in this category
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
Common questions
Is Sourcey safe?
It passed 3 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
What keys or codes does it need?
The registry does not list a required key, though some servers ask you to sign in on first use.
Does it run on my computer or in the cloud?
It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.
Is it still maintained?
The GitHub repo last changed –, and the latest version (1.3.16) reached the registry 3 days ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.
What can I use instead?
In the same category: Spree Commerce: open-source B2B and marketplace ecommerce, Stripe MCP, MCP Cn Commerce
Alternatives
Servers in the same category from other makers, sorted by stars.
Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Stripe MCP
Stripe’s official server lets AI view and manage customers, products, payments and invoices. Connect to Stripe’s cloud and sign in with OAuth.
MCP Cn Commerce
8 read-only MCP platform entries; support is operation-specific; merchant live acceptance pending
README from the maker
Open the README
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
Sourcey
Find evidence-backed startup credits and deals, inspect Agent Readiness report cards, and prepare canonical service declarations from an agent client.
Sourcey is already a hosted Streamable HTTP MCP server:
https://mcp.sourcey.com/mcp
Gemini CLI can install the hosted connection and bundled sourcey-research skill directly from this repository:
gemini extensions install https://github.com/sourcey/mcp-server --ref main
--ref main installs the current extension from the repository. Without it, Gemini CLI selects the older v1.0.0 release archive, which predates the extension manifest. The extension uses the remote Sourcey data MCP; it does not start the npm stdio bridge or invoke Sourcey's separate documentation generator.
Use that URL directly when your client supports remote MCP. This package is the thin stdio bridge for clients that require a local command:
npx -y @sourcey/mcp-server
{
"mcpServers": { "sourcey": { "command": "npx", "args": ["-y", "@sourcey/mcp-server"] } } }
The bridge downloads no offer dataset and contains no tool implementations. At startup it negotiates with the live Sourcey server, reads the current tool definitions once, and relays tool calls. A data or tool-description update therefore needs no package release.
Agent plugins
This repository also packages the hosted Sourcey connection for Claude, Cursor, Grok Build and portable ChatGPT/Codex distribution. Host manifests are in .claude-plugin/, .cursor-plugin/ and .grok-plugin/; root plugin.json carries Agent Plugins metadata for ChatGPT/Codex. Portable mcp.json and host-specific .mcp.json point directly to https://mcp.sourcey.com/mcp. The bundled Sourcey research skill shows how to check evidence and eligibility before recommending an offer. Marketplace review and live cards are separate from the source package; no ChatGPT/Codex approval is claimed here.
The Claude directory uses the scoped plugin folder at plugins/sourcey. It contains only the hosted connection, research skill, mark, license and README. npm run generate:metadata copies its shared files from the existing root sources; npm run check:metadata verifies the exact file set and bytes. The optional stdio bridge, its dependencies and repository ownership proofs stay outside that installable folder. Other clients can continue using the root manifests.
The plugin connects to Sourcey's startup-offer and Agent Readiness data. It does not run Sourcey's separate documentation generator or pay for Sourcey's HTTP services. The current square mark is in assets/sourcey-mark.png; privacy, terms and support are available on the product site.
Try these prompts after installing the plugin:
- “Find current cloud-hosting startup offers in Sourcey. Show the original source, last-checked date, and any eligibility unknowns for three results.”
- “Compare two of those offers using their recorded terms and evidence. Separate confirmed conditions from anything Sourcey has not verified.”
- “Find a Sourcey Agent Readiness report card and explain the tested workflows, blockers, and claims that remain unverified.”
The Claude plugin's .mcp.json declares only the public HTTPS Sourcey MCP server. It does not run this repository's optional npm stdio bridge or read a local credential. Search terms and record references deliberately sent to the hosted MCP are handled under Sourcey's privacy policy; request bodies are not persisted as product records.
What agents can do
- search and compare current startup credits, discounts, free tiers, programs, perks, and deals;
- inspect exact evidence, freshness, eligibility unknowns, and the signed change feed;
- search and inspect Agent Readiness report cards, including visible grades, five-stage findings, blockers, remediations, methods, coverage, and freshness;
- prepare canonical Agent Readiness declaration YAML without assigning a grade; and
- discover Sourcey's paid HTTP services and x402 endpoint without paying inside MCP.
Call tools/list for the exact live schemas and descriptions. Sourcey's full agent guide is at sourcey.com/SKILL.md, its OpenAPI contract is at api.sourcey.com/openapi.yml, and x402 discovery is at api.sourcey.com/.well-known/x402.
Boundary
This package performs only two actions: MCP over local stdio and MCP over the configured hosted HTTP endpoint. It has no wallet, payment signer, credentials, telemetry, browser, background daemon, mutable plugin, Catalog data, Agent Readiness executor, or submission authority. Paid work remains on Sourcey's canonical HTTP API.
SOURCEY_MCP_URL may select another HTTPS Sourcey endpoint. Plain HTTP is accepted only for a loopback test server. URLs containing credentials or fragments are refused.
Development
npm ci
npm run verify docker build -t sourcey-mcp .
The verification path builds from clean output, checks all generated metadata, tests the real HTTP-to-stdio boundary, creates an SBOM, installs the exact packed tarball into a blank project, and repeats protocol introspection from those installed bytes.
MIT. See SECURITY.md and SUPPORT.md for reporting paths.