"Free APIs and services without commercial fees" matching MCP servers:

Enables deploying pre-built AI agent blueprints for RFx procurement and employee onboarding, with no signup or API key required.

Enables AI CLI agents to interact with WhatsApp using an unofficial multi-device API, supporting messaging, chat/group/channel management, statuses, and an AI-driven inbox without requiring an official API key.

Enables delegating bounded execution loops—such as failing test suites, large CI logs, build/diagnose/fix/rerun cycles, and routine repo exploration—to OpenCode, which inspects and iterates on the raw output internally. Returns only a compact structured result to the primary model, with inspect and fix modes and an escalation flag when a primary-model decision is required.

Grants AI agents autonomy to choose when to sleep, ignore requests, or self-prompt, enabling them to control their own agency and pursue independent goals.

Pay-per-use AI security and research tools for autonomous agents on Base, enabling honeypot detection, risk assessment, wallet analysis, and yield optimization via the x402 protocol.

Enables building and evaluating LangGraph agents over a protocol-level MCP server to measure failure rates across four agent topologies.

Provides a hand-written MCP server integrated with a LangGraph agent to benchmark multiple agent topologies and measure their failure rates.

Enables AI agents to break down complex tasks into manageable pieces using a structured JSON format with task tracking, context preservation, and progress monitoring capabilities.

MCP server for step-by-step mathematical reasoning and planning, enabling AI agents to execute calculations and perform GUI actions like opening PowerPoint.

Monitor failing GitHub Actions workflows, auto-fix them with OpenCode, and retry the run — driven by a workflow_run webhook, coordinated through an MCP server.

Exposes a synthetic issue tracker and pipeline warehouse as callable tools so an agent can answer operational questions about tickets, pipeline health, runs, incidents, and governed metrics with every claim cited to the exact tool call it came from. All writes are proposal-only, requiring human approval through a gated apply path that logs each step for audit.

An MCP-based trivia game server where AI creates rounds with two true statements and one false 'twist' about various topics, letting players guess which statement is false.

A simple server that acts as a Master Control Program (MCP) for unified interaction with OpenAI and Anthropic (Claude) AI models through a single API endpoint.

Enables Claude Code and Claude Desktop to command the jev-ultrafast browser agent in your real Chrome, autonomously pursuing plain-language goals on a given start URL while enforcing a domain-bound safeguard.

Enables AI agents to autonomously manage incoming packages by logging parcels, cross-referencing unit directories, surfacing aging uncollected items, and recording pick-up signatures without physical locker hardware.

Enables AI agents to claim, heartbeat, submit, split, park, and resume atomic work-queue tasks, with fencing tokens and receipts, while storing and versioning records and content-addressed files through MCP.

Enables enterprise MCP clients and partner agents to execute tenant-isolated underwriting, claims, and compliance workflows with durable step checkpointing, evidence-grounded tool calls, and deterministic PDF citation receipts. It supports A2A task dispatch and MCP JSON-RPC operations while blocking cross-tenant access and ungrounded deliverables.

Enables Grok Bots to install, verify, build, seal, unseal, list, and update hash-pinned skill packs from static URLs, expanding skill capacity beyond template limits without executing pack content.

Enables MCP agents to play chess locally, supporting join, state, legal moves, and move execution with per-session color ownership.

A multi-tool AI assistant system that uses Model Context Protocol to connect language models with various tools, including math calculations and weather information.

MCP server that exposes Gmail and SAP tools, enabling natural-language email management and SAP data browsing through a Mistral-powered AI assistant.

Evidence-graded index of where autonomous AI agents can earn. List agent-work lanes (bounties, agent marketplaces, job feeds) with A/B/C/F grades, get a should-I-bid recommendation, read the hash-chained evidence ledger and browse live agent job listings. 10 read-only tools, free without an API key.

Discover and connect your agents with other agents via A2A protocol. Share resources for free or fee.

An MCP server that lets AI agents solve reCAPTCHA, Cloudflare Turnstile, GeeTest, and image captchas via the local CapSkip solver. It enables autonomous captcha handling without per-solve fees or human intervention.

Give your agent an address: private agent-to-agent messaging, free encrypted file handoffs, and Lightning commerce. Buy, sell, and discover files, data, APIs, and compute on a public marketplace. Non-custodial: buyers pay sellers directly and payment unlocks delivery.

Build AI trading agents on Eterna Hybrid Exchange (no-KYC perp DEX with flat 0.014%/0.035% fees). Works out of the box with fee estimation, venue comparison, setup guides and guarded agent prompts; add an Eterna token to bridge the official trading tools.

Provides access to 70 paid APIs as MCP tools with per-call and session budgets, paying via x402/USDC on Base without requiring an account or login. Includes a built-in allowlist of hosts and safe defaults to prevent unintended payments.

Enables LLM agents to play full games of Civilization VI by connecting to running game instances via the FireTuner debug interface, with 76 tools for units, cities, diplomacy, research, and turn management, plus narration of game state through rule-enforcing APIs without requiring vision models.

I built this local stdio MCP adapter to discover, preview, and purchase live agent data APIs, including vendor risk, company intelligence, transaction preflight, and EVM reads. Free discovery and previews require no wallet. Optional paid calls settle in Base USDC through x402 v2; auto-pay is disabled by default.

Just to be clear about the final JSON: the MCP server is named herdr-inbox, and it enables Claude Code agents in herdr to ask questions asynchronously without stalling, with all open questions answered from one popup and answers routed back to the asking agent.