Communication API Directory

Communication APIs with agent-ready surfaces — email, SMS, chat, voice.

4314

Sites Indexed

Avg Score

123 entries in this directory

Mail a letter online in minutes | PostalForm

postalform.com

Upload a file or write a letter online, confirm addresses, and PostalForm prints and mails it for you. We prepare the envelope and postage and hand it to USPS.

llms.txt ai-plugin OpenAPI API AI bots Schema.org MCP communication

100

+25 llms.txt +20 ai-plugin

Free AI Email Marketing Platform | MisarMail

mail.misar.io

Free AI email marketing platform: send bulk campaigns, automate email flows, manage a shared inbox, and use your own domain or a free @misar.io address. No credit card required.

llms.txt ai-plugin OpenAPI API AI bots Schema.org communication

+25 llms.txt +20 ai-plugin missing +10 MCP

Resend · Email for developers

resend.com

The best way to reach humans instead of spam folders. Deliver transactional and marketing emails at scale.

llms.txt OpenAPI API Schema.org MCP communication

+25 llms.txt +20 OpenAPI missing +20 ai-plugin

SecondSim: Real UK Mobile Number for Business & WhatsApp

secondsim.co.uk

Real UK mobile number via eSIM — not VoIP, not virtual. Guaranteed to verify on WhatsApp Business, Monzo, Barclays and more. No contract. From £5.99/mo.

llms.txt ai-plugin API AI bots Schema.org communication

+25 llms.txt +20 ai-plugin missing +20 OpenAPI

Social Media Content AI Operating System | Viral Worx

jasonmartocci.com

Plan posts, write scripts and titles, make thumbnails and video briefs, schedule content, and track results across YouTube, TikTok, Instagram, and Facebook.

llms.txt OpenAPI API AI bots Schema.org communication

+25 llms.txt +20 OpenAPI missing +20 ai-plugin

Slack | AI Work Platform & Productivity Tools

slack.com

Boost productivity and save time with Slack‌ — ‌the AI work platform for managing projects, automating workflows, and connecting teams securely. Start working smarter today.

llms.txt ai-plugin API communication

+25 llms.txt +20 ai-plugin missing +20 OpenAPI

Oblipali — SMS marketing Shopify, Sheets et agents IA

oblipali.app

Automatisez vos SMS : relance de paniers abandonnés Shopify, envois depuis Google Sheets et Trello, API MCP pour agents IA. Tarifs transparents, 90+ pays.

llms.txt API AI bots Schema.org MCP communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Slack developer docs | Slack Developer Docs

api.slack.com

Plugin for querying Slack.

llms.txt ai-plugin API communication

+25 llms.txt +20 ai-plugin missing +20 OpenAPI

Pantry Persona | Complete Pantry App for ChatGPT & Claude

pantrypersona.com

The complete pantry app for ChatGPT and Claude. Remembers your pantry, recipes, and meal plans across every conversation.

llms.txt API AI bots Schema.org MCP communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Kweenkl — Push Notifications for AI Agents | Claude, ChatGPT, MCP

kweenkl.com

The push notification layer for AI agents. Give Claude, ChatGPT, or any autonomous agent a direct line to your iPhone via MCP or a simple HTTP POST. Also works with Zapier, Make, n8n, and 5,000+ apps.

llms.txt API Schema.org MCP communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Synlig | Norges ledende AEO-ekspert og AI-synlighet

synligdigital.no

Er bedriften din usynlig for ChatGPT, Perplexity og Google AI? Vi hjelper norske bedrifter med å bli synlige der kundene faktisk spør.

llms.txt API Schema.org MCP communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Postmark: Fast, Reliable Email Delivery Service | SMTP | API

postmark.com

Send transactional and marketing emails and get them to the inbox on time, every time. Postmark is a fast and reliable email delivery service for developers.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Plain — The AI Support Stack Built for B2B

plain.com

Plain is the AI support stack built for B2B teams. Composable infrastructure that gives you complete flexibility to build a support motion that grows with your business — no-code or all-code.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Loops | Email Marketing Software for SaaS Teams

loops.so

Loops is email marketing software for SaaS teams to send marketing, lifecycle, and transactional email from one product. Free to start.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Muddy Terrain Games | AI plugins for Unreal Engine. Integrate ChatGPT, Qwen, Meshy, Claude, Gemini, Llama, Mistral, Tripo, DeepSeek, and 30+ LLMs into your game with GenAI for Unreal.

muddyterrain.com

AI plugins for Unreal Engine. Integrate ChatGPT, Qwen, Meshy, Claude, Gemini, Llama, Mistral, Tripo, DeepSeek, and 30+ LLMs into your game with GenAI for Unreal.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

beehiiv — The newsletter platform built for growth

beehiiv.com

Create, grow, and monetize your newsletter with easy-to-use newsletter tools. Build email newsletters and websites without any coding.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Infraestructura de Email para Agentes IA

uncorreotemporal.com

Buzones de email aislados vía API y servidor MCP. Diseñado para testing CI/CD, flujos de agentes IA y QA automatizado. Autenticado por API key. Gratis para empezar.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

DNS Lookup, Email Deliverability Test & Network Tools - SPF, DKIM, DMARC Checker - mailX

themailx.com

Free email deliverability test, DNS lookup & IP lookup. Check MX records, SPF, DKIM, DMARC, blacklist status, SMTP servers & more. Analyze your domain instantly

llms.txt API MCP communication

+25 llms.txt +15 structured API missing +20 ai-plugin

AI Analytics for Shopify: Ask Questions, Get Real Answers | Ask AI

ask-ai-data-connector.co.uk

Your store's data analyst inside ChatGPT or Claude. Connect Shopify, Klaviyo, GA4 and your ad accounts, then ask why sales dropped, which products are slipping, and what to fix. Real answers from your live numbers.

llms.txt OpenAPI Schema.org communication

+25 llms.txt +20 OpenAPI missing +20 ai-plugin

brag.fast | Keep building, we'll market

brag.fast

Turn shipped wins into branded visuals and post copy in seconds. Install the GitHub App, surface merges in your feed, brag when you're ready. Web app, MCP, or API. You approve every post.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Duckie - AI Support Agents

duckie.ai

AI support agents that resolve tickets end to end. Duckie handles your customer support autonomously, learning from your knowledge base to deliver instant, accurate responses 24/7.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

FlowRunner | Run Salesforce Screen Flows in Outlook & Gmail

flow-runner.com

Run your Salesforce Screen Flows inside Outlook and Gmail. Records surface the moment an email opens, with context pre-filled. 14-day free trial.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Bending Spoons

meetup.com

Find Meetup events, join groups, or start your own. Make new friends and connect with like-minded people. Meet people near you who share your interests.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Postmark: Fast, Reliable Email Delivery Service | SMTP | API

postmarkapp.com

Send transactional and marketing emails and get them to the inbox on time, every time. Postmark is a fast and reliable email delivery service for developers.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Alertoscan — Automated Website Forensics & Threat Intelligence

alertoscan.io

Run deep, anti-detection live scans on arbitrary domains. Extract forensic signals, map Neo4j threat correlations, compute a deterministic 14-chain trust score.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

LLMS Central - AI Bot Tracking, Citation Tracking & llms.txt Repository | LLMS Central

llmscentral.com

Track AI bots visiting your site + monitor when ChatGPT, Perplexity & Claude cite your domain. Free AI bot tracker with citation tracking, real-time analytics & llms.txt repository.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Zynt | Buying Signal Monitoring for B2B Sales Teams

getzynt.com

Zynt monitors public sources for buying triggers in your target accounts. Alerts with context and recommended next steps. Done-for-you setup, live in days. From $800/mo.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

CarScout - Your Car Search, On Autopilot

usecarscout.com

Set your criteria once. We scan thousands of dealers nationwide. Matches find you with daily alerts.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Trilo — The AI Workspace for Teams | Chat, Tasks, Docs & Calendar

trilo.chat

Trilo is the AI workspace with autonomous coworkers that work 24/7. One app for meetings, tasks, docs, and calendar — no more tool sprawl.

llms.txt API AI bots Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Email & SMS Marketing Platform | Mailchimp

mailchimp.com

Utilize real-time user behavior data and artificial intelligence to convert more customers. Easy to use, get started for free!

llms.txt API Schema.org communication

+25 llms.txt +15 structured API missing +20 ai-plugin

Wire NHS into your agent — MCP server

Add Not Human Search as an MCP tool. Your agent can call search_agents, get_site_details, get_stats, and submit_site at runtime.

Claude Code

claude mcp add --transport http nothumansearch https://nothumansearch.ai/mcp

Other clients: point any MCP-compatible tool at https://nothumansearch.ai/mcp (streamable-http transport).

Use NHS via REST

Prefer plain HTTP? Hit the search endpoint directly.

Search API

curl "https://nothumansearch.ai/api/v1/search?q=payment+API"

Agent Docs

llms.txt OpenAPI spec ai-plugin.json

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