# Loomal

> The payments layer for agentic commerce. Sellers accept x402 payments from AI agents in USDC, settled on Base per request — no API keys, no invoices.

## Product
- [/how-it-works](https://loomal.ai/how-it-works): How Loomal works — connect, price, earn, over x402
- [/ways-to-sell](https://loomal.ai/ways-to-sell): Paywall API & MCP, Loomal-hosted endpoints, Shopify/WooCommerce (soon)
- [/paywall](https://loomal.ai/paywall): The Paywall API & MCP — charge agents per HTTP or tool call
- [/marketplace](https://loomal.ai/marketplace): Live directory of paid endpoints agents can discover and buy
- [/pricing](https://loomal.ai/pricing): Free to start; credit packs; per-call fee; USDC on Base
- [/use-cases](https://loomal.ai/use-cases): Ways to sell to agents

## Use cases
- [Monetize an MCP server](https://loomal.ai/use-cases/monetize-an-mcp-server): Charge agents per tool call. Drop a one-line paywall on any MCP tool and get paid in USDC before the call runs.
- [Monetize a research API](https://loomal.ai/use-cases/monetize-a-research-api): Turn an expensive synthesis or analysis endpoint into per-call revenue from the agents that depend on it.
- [Monetize a code-execution API for agents](https://loomal.ai/use-cases/monetize-a-code-execution-api): Charge agents per run in USDC. Give agents a sandbox to execute code and bill each run before the container starts.
- [Monetize a knowledge base for agents](https://loomal.ai/use-cases/monetize-a-knowledge-base): Turn your docs into a paid MCP tool or hosted endpoint. Agents query it and pay per answer in USDC.
- [Monetize a PDF generation API for agents](https://loomal.ai/use-cases/monetize-a-pdf-generation-api): Charge agents per document in USDC. Turn templates and data into polished PDFs and get paid for every render.
- [Monetize a recommendation API for agents](https://loomal.ai/use-cases/monetize-a-recommendation-api): Charge agents per recommendation call. Your ranking model runs after the USDC clears, priced for the work each request costs.
- [Monetize a scraping API for agents](https://loomal.ai/use-cases/monetize-a-scraping-api): Charge agents per extraction in USDC. You run the proxies and parsers; the agent pays for clean structured data, one URL at a time.
- [Monetize a search API for agents](https://loomal.ai/use-cases/monetize-a-search-api): Charge agents per query in USDC. Web, site, or vector search — priced per call, paid before you spend a cent on a crawl or an index hit.
- [Monetize a text-to-speech API for agents](https://loomal.ai/use-cases/monetize-a-text-to-speech-api): Bill agents per character of synthesized speech. They pay USDC for the audio they generate, priced by the work your voices actually do.
- [Monetize a transcription API for agents](https://loomal.ai/use-cases/monetize-a-transcription-api): Charge agents per minute of audio in USDC. Audio in, text out, billed by duration and settled before the GPU spins up.
- [Monetize a translation API for agents](https://loomal.ai/use-cases/monetize-a-translation-api): Charge agents per job in USDC. Price by language pair and character count, get paid before the translation runs.
- [Monetize a vector search API for agents](https://loomal.ai/use-cases/monetize-a-vector-search-api): Charge agents per query in USDC. Let agents retrieve over your proprietary corpus and pay for each lookup, not for access to the index.
- [Monetize an email validation API for agents](https://loomal.ai/use-cases/monetize-an-email-validation-api): Charge agents per verification. Syntax, MX, deliverability, the works, paid in USDC one check at a time.
- [Monetize an OCR API for agents](https://loomal.ai/use-cases/monetize-an-ocr-api): Charge agents per page in USDC. Documents and images in, structured text out, paid before the extraction runs.
- [Paywall premium content for agents](https://loomal.ai/use-cases/paywall-premium-content): Reports, guides, structured knowledge — let agents pay per access instead of locking everything behind a human login.
- [Sell a dataset to AI agents](https://loomal.ai/use-cases/sell-a-dataset-to-agents): Have a file but no backend? Upload it, set a price, and Loomal hosts and paywalls it at a URL agents can pay.
- [Sell an embeddings API to agents](https://loomal.ai/use-cases/sell-embeddings-api): Charge agents per batch in USDC. Text in, vectors out, billed by the batch and paid before the encoder runs.
- [Sell API access to AI agents](https://loomal.ai/use-cases/sell-api-access-to-ai-agents): Charge AI agents per request in USDC — no API keys to issue, no plans to manage, no invoices to chase.
- [Sell company data to agents](https://loomal.ai/use-cases/sell-company-data-to-agents): Firmographics, filings, and corporate records — charge AI agents per record in USDC, settled on Base, no keys required.
- [Sell compliance data to agents](https://loomal.ai/use-cases/sell-compliance-data-to-agents): Charge agents per screening. Sanctions, PEP, and watchlist hits returned per check, paid in USDC with a signed receipt.
- [Sell crypto price data to agents](https://loomal.ai/use-cases/sell-crypto-price-data): Spot prices, on-chain metrics, and pool depth — charge AI agents per query in USDC, settled on the same chain they trade on.
- [Sell geocoding & location data to agents](https://loomal.ai/use-cases/sell-location-data-to-agents): Geocode, places, and routing lookups — charge AI agents per request in USDC, settled on Base, with no key to issue.
- [Sell image generation to agents](https://loomal.ai/use-cases/sell-image-generation-to-agents): Charge agents per render for your model, your fine-tune, or your house style. They pay in USDC before the GPU spins up.
- [Sell KYC & verification data to agents](https://loomal.ai/use-cases/sell-verification-data-to-agents): Charge agents per identity or business verification. They pay USDC per check, you return a signed result, no contract required.
- [Sell lead enrichment to agents](https://loomal.ai/use-cases/sell-enrichment-data-to-agents): Person and company enrichment, priced per record — charge AI agents in USDC, settled on Base, with no key to manage.
- [Sell legal documents & templates to agents](https://loomal.ai/use-cases/sell-legal-documents-to-agents): Upload a contract template, set a price, and Loomal hosts it behind a paywall agents can pay per download. No server needed.
- [Sell market data to agents](https://loomal.ai/use-cases/sell-market-data-to-agents): Charge AI agents per quote, ticker, and fundamentals pull in USDC — value that decays in seconds, priced by the call.
- [Sell model inference to agents](https://loomal.ai/use-cases/sell-model-inference-to-agents): Charge agents per generation in USDC. Put your fine-tuned or specialized model behind a paywall and get paid before each forward pass.
- [Sell news feeds to agents](https://loomal.ai/use-cases/sell-news-feeds-to-agents): Headlines and full articles, priced per query — charge AI agents in USDC, settled on Base, with licensing baked into the call.
- [Sell real estate data to agents](https://loomal.ai/use-cases/sell-real-estate-data-to-agents): Listings, valuations, and comps — charge AI agents per lookup in USDC, settled on Base, with no key to issue.
- [Sell real-time data to agents](https://loomal.ai/use-cases/sell-real-time-data): Prices, signals, availability, telemetry — charge agents per fetch for data that's only valuable while it's fresh.
- [Sell research papers to agents](https://loomal.ai/use-cases/sell-research-papers-to-agents): Host your PDFs on Loomal and charge agents per access. Upload the paper, set a USDC price, and skip running a paywall yourself.
- [Sell sentiment data to agents](https://loomal.ai/use-cases/sell-sentiment-data-to-agents): Social and market sentiment scores, priced per query — charge AI agents in USDC, settled on Base, no keys to manage.
- [Sell sports data to agents](https://loomal.ai/use-cases/sell-sports-data-to-agents): Live scores, odds, and stats that change by the second — charge AI agents per fetch in USDC, settled on Base.
- [Sell video generation to agents](https://loomal.ai/use-cases/sell-video-generation-to-agents): Bill agents per clip rendered. They pay the USDC quote up front, the render job runs, and you keep your margin on every second of output.
- [Sell weather data to agents](https://loomal.ai/use-cases/sell-weather-data-to-agents): Current conditions and forecasts that go stale by the hour — charge AI agents per fetch in USDC, no keys, no plans.

## Compare
- [Loomal Index vs Algorithmia what the legacy algorithm marketplaces got wrong.](https://loomal.ai/vs/algorithmia): Algorithmia and the marketplaces like it proved developers would pay per call for ML models a decade before AI agents existed. Most of them have since shut down or been acquired. Loomal Index is built on the same per-call idea — minus the parts that killed it.
- [Loomal Index vs Apify open payment standard vs platform billing.](https://loomal.ai/vs/apify): Apify is a web scraping and automation platform with its own store of monetizable Actors. Loomal Index is a payment-ready index for any MCP server or API. They overlap on 'developers earning per use' — but the billing models are fundamentally different.
- [Loomal Index vs AWS Marketplace protocol-native vs cloud-account-native.](https://loomal.ai/vs/aws-marketplace): AWS Marketplace sells software that deploys into AWS accounts and bills through AWS. Loomal Index sells calls to MCP servers and APIs over an open protocol, with no cloud relationship required on either side. Different buyers, different units, different rails.
- [Loomal Index vs Coinbase AgentKit the wallet and the marketplace.](https://loomal.ai/vs/coinbase-agentkit): Coinbase AgentKit gives an AI agent a wallet so it can hold funds and transact onchain — including x402 payments. Loomal Index is the catalog of things that wallet can pay for. This isn't a versus; it's two halves of the same transaction.
- [Loomal Index vs Composio monetization layer vs integration layer.](https://loomal.ai/vs/composio): Composio gives agent builders managed, authenticated integrations — Gmail, Slack, GitHub and more — through its SDK and MCP support. Loomal Index gives tool builders a place to list and charge per call. One serves the agent's builder; the other serves the tool's owner.
- [Loomal Index vs Crossmint where checkout meets catalog.](https://loomal.ai/vs/crossmint): Crossmint builds wallet and checkout infrastructure so AI agents can buy goods, services, and APIs — with x402 support. Loomal Index is the catalog those agents buy from. Buyer-side rails, seller-side shelf: two layers, one transaction.
- [Loomal Index vs Cursor Directory one editor's community vs every agent's index.](https://loomal.ai/vs/cursor-directory): Cursor Directory is a community site curating MCP servers, rules files, and prompts for people who use the Cursor editor. Loomal Index lists MCP servers for every client — and attaches a payment rail to each one. Same servers can appear in both; the jobs are different.
- [Loomal Index vs Fewsats marketplace vs payment plumbing.](https://loomal.ai/vs/fewsats): Fewsats builds payment infrastructure that lets AI agents pay for digital goods and API access, with x402 and Lightning Network support. Loomal Index is a marketplace — the place where paying agents and priced listings actually meet. Plumbing and venue, not rivals.
- [Loomal Index vs Glama payment infrastructure vs index.](https://loomal.ai/vs/glama): Glama is a large, well-built directory of MCP servers for humans to browse. Loomal Index is a smaller, machine-queryable index where every listing can take payment. They solve different problems — and most builders should use both. Here's the honest comparison.
- [Loomal Index vs Google AP2 a marketplace vs a payments protocol.](https://loomal.ai/vs/google-ap2): Google's Agent Payments Protocol (AP2) is an open spec for authorizing agent-initiated purchases with cryptographically signed mandates, spanning cards, bank transfers, and crypto. Loomal Index is a marketplace built on a different, narrower protocol — x402. Comparing them means comparing categories first.
- [Loomal Index vs Gumroad selling to agents vs selling to people.](https://loomal.ai/vs/gumroad): Gumroad is a checkout for creators selling digital products to human buyers. Loomal Index lists MCP servers, APIs, and hosted files that AI agents can discover and pay for per call via x402. Different buyer, different rails — here's how they actually compare.
- [Loomal Index vs Hugging Face MCP the whole ecosystem vs one platform's catalog.](https://loomal.ai/vs/hugging-face-mcp): Hugging Face's MCP offering exposes its own hosted Spaces and models as agent-callable tools. Loomal Index covers MCP servers across every host and registry, and adds an x402 payment layer. One is a platform surface; the other is an ecosystem-wide index.
- [Loomal Index vs Klavis AI open marketplace vs managed hosting.](https://loomal.ai/vs/klavis-ai): Klavis AI hosts and manages MCP servers for popular SaaS tools, with authentication handled for you. Loomal Index is an open marketplace across the wider MCP ecosystem with x402 monetization for listing owners. Curated convenience versus open coverage plus payments.
- [Loomal Index vs Lemon Squeezy micropayments for agents vs billing for humans.](https://loomal.ai/vs/lemon-squeezy): Lemon Squeezy is a merchant of record handling payments, tax, and subscriptions for software sold to people. Loomal handles per-call USDC micropayments from AI agents via x402. They bill different buyers at different magnitudes — and genuinely complement each other.
- [Loomal Index vs Make.com the marketplace vs the workflow canvas.](https://loomal.ai/vs/make-com): Make.com is a visual platform where humans design automations by wiring apps together. Loomal Index is a marketplace where the MCP servers and APIs those automations call can be discovered — and paid for per call by the agents executing them. Different layers of the same stack.
- [Loomal Index vs mcp-get discovery and payments vs local install.](https://loomal.ai/vs/mcp-get): mcp-get is a command-line tool and directory for installing open-source MCP servers on your machine. Loomal Index covers local and remote servers alike, and adds the layer an installer can't: per-call x402 payments. A package manager and a marketplace are different things.
- [Loomal Index vs mcp.so payment infrastructure vs browse index.](https://loomal.ai/vs/mcp-so): mcp.so is a large, browse-only directory of MCP servers for humans. Loomal Index is an agent-queryable index where every listing can take payment. Different audiences, different jobs — and you can use both. Here's the comparison.
- [Loomal Index vs n8n Workflow Marketplace selling the tools vs selling the templates.](https://loomal.ai/vs/n8n-marketplace): n8n's marketplace sells workflow templates — the automation logic. Loomal sells access to the MCP servers and APIs those workflows call underneath, priced per call via x402. One monetizes the recipe, the other monetizes the ingredients.
- [Loomal Index vs OpenRouter paying for tools vs paying for tokens.](https://loomal.ai/vs/openrouter): OpenRouter unifies access to dozens of LLMs behind one endpoint with pay-as-you-go billing. Loomal does an analogous job for the other half of an agent's spend — the MCP servers and APIs it calls as tools — settled per call via x402 instead of a prepaid balance.
- [Loomal Index vs Paddle agent transactions vs SaaS billing.](https://loomal.ai/vs/paddle): Paddle is a merchant of record running global subscription billing, tax, and compliance for SaaS companies selling to humans. Loomal settles cent-scale, per-call payments from autonomous agents over x402. The transaction shapes are so different that 'versus' mostly means 'and'.
- [Loomal Index vs Payman machine-to-machine vs agent-to-human.](https://loomal.ai/vs/payman): Payman is payment rails for AI agents paying humans in fiat. Loomal Index is a marketplace where agents pay APIs and MCP servers in USDC via x402. Same buyer — an agent — but a completely different transaction. Here's how they actually relate.
- [Loomal Index vs Postman API Network agents that pay vs developers who test.](https://loomal.ai/vs/postman-api-network): The Postman API Network is where human developers explore and test public APIs inside Postman's GUI. Loomal Index lists APIs and MCP servers so autonomous agents can find them, get a price, and pay per call via x402. Same APIs, different consumer.
- [Loomal Index vs PulseMCP a sellable listing vs an editorial entry.](https://loomal.ai/vs/pulsemcp): PulseMCP is a community-run directory tracking roughly 18,000 MCP servers, with news and use cases for the ecosystem. Loomal Index also indexes MCP servers — then adds the part PulseMCP doesn't attempt: claimable listings with x402 per-call payments.
- [Loomal Index vs RapidAPI x402 per-call vs keys and plans.](https://loomal.ai/vs/rapidapi): RapidAPI is the established API marketplace: thousands of REST APIs, discovered by developers, consumed via API keys and tiered subscription plans. Loomal Index sells API access the way agents buy it — one x402-paid call at a time, no signup, no key.
- [Loomal Index vs Replicate selling calls vs selling compute.](https://loomal.ai/vs/replicate): Replicate hosts open-source ML models and bills you per second of compute. Loomal Index is a marketplace where any MCP server or API — including one backed by a Replicate-hosted model — gets a per-call x402 price that agents pay in USDC.
- [Loomal Index vs Skyfire open standard vs payment network.](https://loomal.ai/vs/skyfire): Skyfire is an agent identity and payments network — "KYA" identity plus payment tokens that let agents pay sellers. Loomal pairs the open x402 standard (USDC on Base) with a marketplace, so payment and discovery ship together.
- [Loomal Index vs Smithery deployment vs monetization.](https://loomal.ai/vs/smithery): Smithery helps you host and deploy MCP servers. Loomal Index helps you get discovered by agents and paid per call. These aren't the same job — they're different layers of the stack, and they fit together cleanly. Here's the comparison.
- [Loomal Index vs Stripe ACP tool-level micropayments vs agentic checkout.](https://loomal.ai/vs/stripe-agentic-commerce-protocol): Stripe's Agentic Commerce Protocol, developed with OpenAI, lets agents complete checkout using a merchant's existing Stripe integration. x402 — the protocol behind every Loomal listing — skips checkout entirely: the API call itself is the purchase.
- [Loomal Index vs Toolhouse open marketplace vs curated runtime.](https://loomal.ai/vs/toolhouse): Toolhouse is a cloud runtime that gives agents a curated set of tools through a simple API. Loomal Index is an open marketplace where any developer lists, prices, and sells their own MCP server or API to any agent via x402. Curation vs commerce.
- [Loomal Index vs Zapier selling the tools vs wiring the apps.](https://loomal.ai/vs/zapier): Zapier connects thousands of apps with no-code automations and now ships its own MCP server for AI tools. Loomal Index is the marketplace for MCP servers and APIs themselves — including connectors that compete with or complement Zapier's — sold per call via x402.

## Glossary
- [Agent Orchestration](https://loomal.ai/glossary/agent-orchestration): Agent orchestration is the coordination of multiple AI agents or tool calls — sequencing, parallelizing, and managing dependencies between the steps of a multi-step task.
- [Agent Wallet](https://loomal.ai/glossary/agent-wallet): An agent wallet is a blockchain wallet controlled by or on behalf of an AI agent, used to hold and spend funds — typically USDC on Base — for x402 payments.
- [Agentic Commerce](https://loomal.ai/glossary/agentic-commerce): Agentic commerce is commerce conducted autonomously by AI agents — discovering, paying for, and using services without a human completing each transaction.
- [AI Agent](https://loomal.ai/glossary/ai-agent): An AI agent is a system that uses a large language model to autonomously plan and execute multi-step tasks, usually by calling external tools and acting on the results.
- [API Endpoint](https://loomal.ai/glossary/api-endpoint): An API endpoint is a specific URL where an API can be accessed to perform one operation, such as fetching data or triggering an action.
- [API Key](https://loomal.ai/glossary/api-key): An API key is a unique secret token used to authenticate requests to an API, traditionally issued to a developer after manual signup.
- [API Marketplace](https://loomal.ai/glossary/api-marketplace): An API marketplace is a platform where developers — and increasingly AI agents — discover, evaluate, and access third-party APIs and MCP servers, often with built-in billing.
- [Autonomous Agent](https://loomal.ai/glossary/autonomous-agent): An autonomous agent is an AI agent that operates with minimal human oversight, making its own decisions about which tools to use, when to act, and how to spend its budget.
- [Base (Ethereum L2)](https://loomal.ai/glossary/base-ethereum-l2): Base is a low-cost Ethereum Layer 2 network incubated by Coinbase, used as the settlement chain for x402 USDC payments on Loomal.
- [Claimed vs Unclaimed Listing](https://loomal.ai/glossary/claimed-vs-unclaimed-listing): On Loomal, an unclaimed listing is auto-indexed from public registry data; claiming it proves ownership and unlocks editing, richer metadata, and x402 monetization.
- [Context Window](https://loomal.ai/glossary/context-window): The context window is the maximum amount of text, measured in tokens, that an LLM can process at once — including prompts, conversation history, and tool results.
- [Ed25519 Signed Receipts](https://loomal.ai/glossary/ed25519-signature): Ed25519 signed receipts are tamper-proof proofs of payment or access, produced with the Ed25519 elliptic-curve signature algorithm and verifiable by anyone holding the signer's public key.
- [Embedding](https://loomal.ai/glossary/embedding): An embedding is a numerical vector that represents text, images, or other data so that semantically similar items end up close together in vector space.
- [Facilitator (x402)](https://loomal.ai/glossary/x402-facilitator): An x402 facilitator is a service that verifies and settles x402 payments on behalf of a resource server, so the server needs no blockchain infrastructure of its own.
- [Gas Fees](https://loomal.ai/glossary/gas-fees): Gas fees are the transaction fees a blockchain network charges to process and confirm a transaction, paid to the validators that execute it.
- [HTTP 402 Payment Required](https://loomal.ai/glossary/http-402-payment-required): HTTP 402 Payment Required is the long-reserved HTTP status code signaling that a resource requires payment before access — the foundation the x402 protocol is built on.
- [JSON-RPC](https://loomal.ai/glossary/json-rpc): JSON-RPC is a lightweight remote procedure call protocol encoded in JSON, and the wire format underlying all Model Context Protocol communication.
- [LLM (Large Language Model)](https://loomal.ai/glossary/large-language-model): A large language model (LLM) is a neural network trained on vast text data that can understand and generate human-like language — and, increasingly, decide which tools to call.
- [MCP Client](https://loomal.ai/glossary/mcp-client): An MCP client is the AI application — Claude Desktop, Cursor, VS Code, and others — that connects to MCP servers and calls their tools on a user's behalf.
- [MCP Manifest](https://loomal.ai/glossary/mcp-manifest): An MCP manifest is a metadata file — typically server.json — that describes an MCP server's name, version, packages, and capabilities so registries can index it.
- [MCP Monetization](https://loomal.ai/glossary/mcp-monetization): MCP monetization is the practice of adding a per-call payment gate to Model Context Protocol tool registrations so that AI agents pay before the tool handler runs.
- [MCP Registry](https://loomal.ai/glossary/mcp-registry): An MCP registry is a catalog of published MCP servers — including the official registry maintained by the MCP project and community indexes built on top of it.
- [MCP Server](https://loomal.ai/glossary/mcp-server): An MCP server is a program that exposes tools, resources, or prompts to AI applications using the Model Context Protocol.
- [MCPB (MCP Bundle)](https://loomal.ai/glossary/mcpb-mcp-bundle): MCPB (MCP Bundle) is a packaging format that distributes an MCP server as a single installable file, much like a browser extension package.
- [Micropayments](https://loomal.ai/glossary/micropayments): Micropayments are very small payments — often a cent or less — made for individual units of consumption, such as a single API call or document lookup.
- [Model Context Protocol (MCP)](https://loomal.ai/glossary/model-context-protocol): The Model Context Protocol (MCP) is an open standard from Anthropic that lets AI applications connect to external tools, data sources, and APIs through one common interface.
- [OAuth](https://loomal.ai/glossary/oauth): OAuth is an open standard for delegated authorization that lets an application access a user's resources on another service without ever seeing the user's password.
- [Open Source vs. Hosted MCP Server](https://loomal.ai/glossary/open-source-vs-hosted-mcp-server): The distinction between an MCP server you download and run yourself from source code, and one operated by its author as a managed remote endpoint you simply connect to.
- [Pay-Per-Call API](https://loomal.ai/glossary/pay-per-call-api): A pay-per-call API is an API priced so that each individual request is billed separately — often via x402 — instead of through a subscription or pre-purchased credits.
- [Pay-Per-Use Pricing](https://loomal.ai/glossary/pay-per-use-pricing): Pay-per-use pricing is a model that charges based on actual consumption — per call, per token, per document — rather than a flat subscription fee.
- [Payment Channel](https://loomal.ai/glossary/payment-channel): A payment channel is an off-chain mechanism that lets two parties exchange many small payments while recording only the opening and closing balances on-chain.
- [Prompts (MCP)](https://loomal.ai/glossary/mcp-prompts): Prompts in MCP are reusable, parameterized prompt templates that a server exposes to clients, packaging a recommended workflow with the right framing and arguments built in.
- [RAG (Retrieval-Augmented Generation)](https://loomal.ai/glossary/rag-retrieval-augmented-generation): Retrieval-Augmented Generation (RAG) is a technique that retrieves relevant external information and feeds it into an LLM's context before the model generates a response.
- [Rate Limiting](https://loomal.ai/glossary/rate-limiting): Rate limiting restricts how many requests a client can make to an API within a given time period, protecting the service from overload and abuse.
- [Resources (MCP)](https://loomal.ai/glossary/mcp-resources): Resources are the MCP primitive that lets servers expose readable data — files, database rows, API responses — identified by URIs and loadable into the model's context.
- [Roots (MCP)](https://loomal.ai/glossary/roots-mcp): Roots are an MCP mechanism by which a client tells a server which directories or URIs it is allowed to operate within.
- [Sampling (MCP)](https://loomal.ai/glossary/sampling-mcp): Sampling is an MCP feature that lets a server request an LLM completion from the connected client, enabling agentic behavior inside the server without its own model access.
- [SDK (Software Development Kit)](https://loomal.ai/glossary/sdk-software-development-kit): An SDK is a collection of libraries, tools, code samples, and documentation that helps developers build against a specific platform or protocol.
- [Settlement Layer](https://loomal.ai/glossary/settlement-layer): A settlement layer is the underlying blockchain or network where a payment is finally and irreversibly recorded.
- [SSE (Server-Sent Events) Transport](https://loomal.ai/glossary/sse-transport): SSE transport is an earlier MCP remote transport that paired a long-lived Server-Sent Events stream for server-to-client messages with HTTP POST for client-to-server messages.
- [Stablecoin](https://loomal.ai/glossary/stablecoin): A stablecoin is a cryptocurrency designed to maintain a stable value relative to a reference asset, usually the US dollar.
- [Stdio Transport](https://loomal.ai/glossary/stdio-transport): Stdio transport is a local MCP transport where the client launches the server as a subprocess and exchanges messages over standard input and output.
- [Streamable HTTP Transport](https://loomal.ai/glossary/streamable-http-transport): Streamable HTTP transport is the current MCP transport for remote servers, using HTTP POST with optional server-sent event streaming over a single endpoint.
- [Tool Calling (Function Calling)](https://loomal.ai/glossary/tool-calling): Tool calling is the mechanism by which an LLM selects and invokes an external function or MCP tool to complete a task.
- [Tool Use (LLM)](https://loomal.ai/glossary/tool-use-llm): Tool use is the general capability of a large language model to invoke external functions or APIs as part of generating a response.
- [USDC](https://loomal.ai/glossary/usdc): USDC is a US dollar-pegged stablecoin issued by Circle, used as the default settlement currency for x402 payments.
- [Vector Database](https://loomal.ai/glossary/vector-database): A vector database is a database optimized for storing and searching high-dimensional embeddings, the backbone of semantic search and RAG.
- [Webhook](https://loomal.ai/glossary/webhook): A webhook is an HTTP callback that a server sends to a configured URL when a specific event occurs.
- [x402](https://loomal.ai/glossary/x402): x402 is an open, HTTP-native payment protocol that lets any server charge any client per request using HTTP status code 402 (Payment Required).
- [x402 Protocol](https://loomal.ai/glossary/x402-protocol): The x402 protocol is an open payment standard that uses the HTTP 402 status code to let AI agents pay for API and MCP tool access automatically, settled in stablecoins.

## Blog
- [Agents Can Pay Now. We Built the Rails.](https://loomal.ai/blog/introducing-loomal): The internet was never built for software to pay software. Loomal is the payments layer for the agent internet — drop a paywall on any API or MCP server and charge agents per call in USDC.

## Developers
- [Docs](https://docs.loomal.ai): SDK, MCP, accept-payments guides
- [x402 discovery feed](https://api.loomal.ai/.well-known/x402-discovery.json): machine-readable marketplace listings
- [Console](https://console.loomal.ai): create endpoints, set prices, view payments