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📖 The AI Tool Bible

OpenAI

San Francisco, US· founded 2015· series-e+· website ↗

Research and product lab behind ChatGPT, GPT-5, DALL-E, Sora, Codex, and the OpenAI API. Founded by Sam Altman, Greg Brockman, Ilya Sutskever, and others; deeply capitalised by Microsoft. Sets the pace on frontier LLMs for most of the industry.

60 tools in the directory

G4

GPT-4o

Featured
Writing · GPT-4o
9.4

OpenAI's multimodal flagship behind ChatGPT.

Freemium· Basic: $10 · Pro: $30 · Enterprise: Contact salesgeneral writingsummarization
SO

Sora

Featured
Video · Sora
8.8

OpenAI's flagship text-to-video model.

Paid· Basic: $10 · Pro: $25 · Enterprise: Contact salesrealistic motionnarrative clips
DE

DALL·E 3

Image Generation · DALL·E 3
8.6

OpenAI's image model — strong on prompt adherence and text-in-image.

Freemium· Basic: $10 · Pro: $20postersinfographics
WH

Whisper

Audio · Whisper large-v3
8.6

OpenAI's open-source speech-to-text — the de-facto baseline.

Free· Free open weights; $0.006/min via OpenAI APItranscriptionself-hosted
OF

OpenAI Fine-tuning

Fine-tuning · GPT-4o-mini / GPT-3.5
8.4

Fine-tune GPT-4o-mini and friends on your own data.

Paid· Basic: $10 · Pro: $25 · Enterprise: Contact salesstyleformat
HE

Helicone

Evaluation · Platform (any LLM)
8.3

Open-source LLM observability — one-line proxy install.

Freemium· Free 100k req/mo; Pro from $25/moobservabilitycost tracking
LS

LM Studio

Agents · Multi-model (gpt-oss, Qwen3, Gemma, DeepSeek-R1, Llama, others)
8.3

Desktop app for discovering, downloading, and running open-weight LLMs locally with an OpenAI-compatible server.

Freemium· Free: $0local-llm-inferenceprivate-chat
JA

Jan

Writing · Multi-model (local open-weights + OpenAI/Claude/Gemini via API)
8.2

Open-source desktop ChatGPT alternative that runs local LLMs and routes to cloud providers from one app.

Free· Free and open source; bring-your-own keys for cloud modelslocal-llm-chatprivate-ai-assistant
LI

LibreChat

Writing · Multi-model (OpenAI, Anthropic, Google, AWS Bedrock, Azure, Ollama, and others)
8.2

Open-source, self-hostable ChatGPT-style frontend that brings every major LLM provider under one roof.

Free· Free and open source; self-hosted (you pay model providers for API usage)multi-model chatself-hosted chatgpt
OP

OpenAI Playground

Writing · Multi-model (GPT-4o, GPT-4.1, o-series, DALL-E, Whisper, TTS)
8.2

OpenAI's official browser sandbox for prompting, tuning, and testing every model on the platform before you ship API code.

Paid· Basic: $10 · Pro: $20 · Enterprise: Contact salesprompt-engineeringmodel-comparison
PO

Poe

Writing · Multi-model (GPT, Claude, Gemini, DeepSeek, FLUX, Sora, others)
8.2

One subscription, every frontier model - Quora's multi-model chat hub with bots, image, video, and audio generation.

Freemium· Basic: $10 · Pro: $20 · Enterprise: Contact salesmulti-model chatimage generation
SG

SGLang

Fine-tuning · Multi-model (DeepSeek, Qwen, Llama, Mistral, GLM, GPT-OSS)
8.2

Open-source high-throughput inference engine for LLMs and multimodal models with OpenAI-compatible serving.

Free· Free, open-source (Apache 2.0); self-hosted infra cost onlyllm-servingmultimodal-inference
AA

Athina AI

Evaluation · Multi-model
8.1

Collaborative LLM evaluation and observability platform for teams shipping AI features to production.

Freemium· Starter free (10k logs/mo); Pro & Enterprise customllm-evaluationprompt-management
CU

Cube

RAG · Multi-model
8.1

Semantic layer that grounds LLM agents in your real business metrics instead of letting them hallucinate SQL.

Freemium· Cube Core open source; Cube Cloud paid, contact salessemantic-layerembedded-analytics
LC

Le Chat

Writing · Mistral Medium 3.5 / Small 4 / Voxtral
8.1

Mistral's ChatGPT-style assistant, now an agent that browses, codes, and plugs into your work tools.

Freemium· Basic: $10 · Pro: $20 · Enterprise: Contact saleschat-assistantdeep-research
LO

LocalAI

Writing · Multi-model (llama.cpp, diffusers, whisper, etc.)
8.1

Self-hosted OpenAI-compatible API for running LLMs, image, and audio models on your own hardware.

Free· Free and open source (MIT)local-llm-inferenceopenai-api-replacement
NI

NightCafe

Image Generation · Multi-model (Flux, DALL-E 3, Ideogram, SDXL, Imagen, Runway, Kling)
8.1

Multi-model AI art generator with a heavy social-network bent and daily community challenges.

Freemium· Basic: $10 · Pro: $20 · Enterprise: Contact salestext-to-imageai-video
OE

OpenAI Evals

Evaluation · OpenAI GPT models (extensible)
8.1

OpenAI's open-source framework for benchmarking LLMs against a shared registry of evaluations.

Free· Free (MIT); you pay OpenAI API costs for eval runsllm-benchmarkingregression-testing
PY

PyGPT

Writing · Multi-model (GPT-5, Claude, Gemini, Grok, DeepSeek, Mistral, Ollama)
8.1

Open-source desktop AI assistant that wires every major LLM provider into one local app with agents, vision, and a code interpreter.

Free· Free and open-source (MIT); bring your own provider API keysdesktop-ai-assistantchat-with-files
CA

CAMEL-AI

Agents · Multi-model
8.0

Open-source Python framework for building multi-agent systems and synthetic data pipelines.

Free· Free, open-source; pay for the underlying LLM API callsmulti-agent-systemssynthetic-data-generation
CH

ChatGPT

Writing · GPT-4o, GPT-4.1, o-series reasoning models
8.0

OpenAI's flagship conversational assistant, and the default benchmark every other chatbot is measured against.

Freemium· Basic: $10 · Pro: $20 · Enterprise: Contact saleswritingcoding
NO

NovelCrafter

Writing · Multi-model (BYO key: OpenAI, Anthropic, Gemini, Mistral, OpenRouter, Ollama)
8.0

Bring-your-own-key novel-writing workspace with a wiki-style codex and multi-model AI assistance.

Freemium· Basic: $10 · Pro: $20 · Enterprise: Contact salesnovel-writingworldbuilding
PG

pgMagic

Coding · OpenAI (user-supplied API key)
8.0

Mac desktop client that lets you chat with your Postgres database in natural language using your own OpenAI key.

Paid· AU$22 one-time license; bring your own OpenAI API keynatural-language-to-sqlpostgres-client
PR

PromptHub

Writing · Multi-model (OpenAI, Anthropic, Google, Meta, Mistral, Bedrock, Azure)
8.0

Git-style prompt management, testing, and deployment platform for teams running multiple LLMs in production.

Freemium· Free signup; paid team plans (contact sales / in-app)prompt-managementprompt-versioning
RE

Reflect

Writing · OpenAI GPT-4 + Whisper
8.0

Networked note-taking app with GPT-4 and Whisper baked into the writing surface.

Paid· Free: Free · Pro: $20 · Business: $35note-takingvoice transcription
AN

AnythingLLM

RAG · Multi-model
7.9

Open-source desktop and self-hosted app that turns your documents into a private chat-and-agent workspace.

Freemium· Basic: $50/monthly · Pro: $99/monthly · Enterprise: Contact Usdocument-chatprivate-rag
LS

LLM Stats

Evaluation · Multi-model
7.9

Live leaderboard and side-by-side comparison hub for 300+ frontier LLMs across reasoning, coding, and multimodal benchmarks.

Free· Free to browse; underlying model usage billed by each providermodel-comparisonbenchmark-tracking
PR

PromptLayer

Evaluation · Platform (any LLM)
7.9

Lightweight prompt logging + management for OpenAI/Claude apps.

Freemium· Free: $0 · Pro: $49 · Team: $500 · Enterprise: Customprompt loggingversioning
PR

PromptHero

Image Generation · Multi-model (Stable Diffusion, Midjourney, DALL-E, Sora)
7.7

Searchable prompt library and image generator for Midjourney, Stable Diffusion, DALL-E and other image/video models.

Freemium· Free tier; PRO ~$24.66/mo billed yearly (7,200 credits)prompt-discoverytext-to-image
HE

Headroom

Agents · Model-agnostic (Anthropic, OpenAI, Vertex, Bedrock, Azure, 100+ via LiteLLM)
7.4

Open-source context compression layer that strips 70-95% of boilerplate before it hits your LLM.

Free· Apache 2.0 open source; free for commercial usetoken-compressionagent-context
MC

Model Context Protocol

Agents · Model-agnostic
7.4

Open standard that lets AI apps plug into data sources, tools, and workflows like USB-C for LLMs.

Free· Free and open source (MIT)agent-toolingide-integrations
OS

OpenAI Swarm

Agents · OpenAI models (designed for, but extensible)
7.4

Lightweight multi-agent orchestration in Python.

Free· Free / open-sourceeducationprototyping
OP

OpenCLI

Agents · GPT-3, GPT-2
7.4

Open-source bridge that hands your already-logged-in Chrome session to a CLI and AI agents.

Free· Free and open-source (Apache-2.0)browser-automationagent-tooling
VO

Voicebox

Audio · Multi-model (Chatterbox, Qwen TTS, Whisper, etc.)
7.4

Open-source desktop voice studio for local cloning, dictation, and giving MCP agents a voice.

Free· Free and open source; optional $VOICEBOX token donationsvoice-cloningtext-to-speech
AG

AgentMemory

Agents · Multi-model (Claude, Gemini, MiniMax, OpenRouter)
7.3

Open-source persistent memory runtime for AI coding agents, with hybrid retrieval and zero external dependencies.

Free· Free, open-source (Apache 2.0); bring your own LLM API keyagent-memorycoding-agents
BI

Bifrost

Agents · Multi-model (OpenAI, Anthropic, Bedrock, Vertex, 1000+ via providers)
7.3

Open-source AI gateway that unifies 1000+ models behind one OpenAI-compatible endpoint with failover, budgets, and MCP routing.

Freemium· Free Forever: Free · Enterprise: Contact salesllm-gatewaymulti-provider-routing
CA

CAI

Agents · Multi-model (incl. alias1, GPT, Claude, DeepSeek)
7.3

Open-source agent framework for offensive security, bug bounty automation, and AI-driven penetration testing.

Freemium· Open source free; CAI PRO ~EUR 350/mopenetration-testingbug-bounty
GP

Guizang PPT Skill

Agents · Multi-model (Claude, Codex, GPT-Image)
7.3

Claude Code / Codex agent skill that generates single-file HTML slide decks in editorial-magazine or Swiss-design styles.

Free· Free, AGPL-3.0; requires a host AI agent (Claude Code, Codex, etc.)html-slide-deckspresentation-design
KA

Kong AI Gateway

Agents · Multi-model
7.3

Enterprise API gateway extended to route, govern, and observe LLM and agent traffic across providers.

Freemium· Free trial: $0 · Plus: Charged per Gateway per month · Enterprise: Custom pricing · Essentials: $0 · Pro: $12llm-gatewaymulti-llm-routing
OP

OpenRouter

Coding · Multi-model
7.3

Unified API gateway to 400+ LLMs from 70+ providers, with one OpenAI-compatible endpoint and automatic failover.

Freemium· Pay-as-you-go credits; sample packs $10 and $99; some free-tier models availablellm-routingmulti-model-access
AF

AI-Flow

Agents · Multi-model (OpenAI, Anthropic, Google, Replicate, xAI)
7.2

Visual node-based builder for chaining OpenAI, Anthropic, Replicate and other model APIs into content pipelines.

Freemium· Free tier: 25 welcome credits + 20 BYOK runs/day; paid plans for extended storageworkflow-automationcontent-pipelines
CS

ChatGPT Shortcut

Writing · Multi-model
7.2

Curated, one-click prompt library covering ChatGPT, Claude, Gemini, and DeepSeek across writing, coding, and academic tasks.

Free· Free; open-source on GitHubprompt-libraryprompt-engineering
CS

Cherry Studio

Agents · Multi-model
7.2

Open-source desktop AI client that wires 300+ LLMs into one chat, knowledge-base, and agent workspace.

Free· Free and open source; bring your own API keysmulti-model chatlocal knowledge base
LB

LLM by Datasette

Coding · Multi-model
7.2

A CLI and Python library for running prompts against any LLM provider and logging everything to SQLite.

Free· Free and open source (Apache 2.0); pay underlying model providers separatelycli-promptingprompt-logging
OD

Open Deep Research

Agents · o3-mini (default), DeepSeek R1, or any OpenAI-compatible model
7.2

Minimal open-source deep-research agent that iteratively searches, scrapes, and reasons to produce cited markdown reports.

Free· Free (MIT); bring your own Firecrawl + LLM API keysdeep-researchagent-scaffolding
PA

Portkey AI Gateway

Agents · Multi-model (1,600+ LLMs)
7.2

Open-source AI gateway that routes a single API call across 1,600+ LLMs with caching, fallbacks, and observability.

Freemium· Developer: Free Forever · Production: $49/month · Enterprise: Custom Pricingllm-routingfallbacks-and-retries
PR

Promptfoo

Evaluation · Multi-model
7.2

Open-source eval and red-teaming framework for LLM apps, prompts, and RAG pipelines.

Freemium· Community: Free · Enterprise: Custom · On-Premise: Customllm-evalsred-teaming
VI

Vibe

Audio · OpenAI Whisper (via whisper.cpp)
7.2

Offline desktop transcription app powered by Whisper, with diarization, batch processing, and an HTTP API.

Free· Free and open-source (MIT)transcriptionsubtitles
CR

Craiyon

Image Generation · Proprietary Craiyon model (descendant of DALL-E Mini)
7.1

Free, no-login AI image generator that prioritises unlimited generations over fidelity.

Freemium· Unterstützer: $10 · Professionell: $20 · Ultra: $70text-to-imagememe-generation
GR

Groq

Coding · Multi-model (Llama, Mixtral, Gemma, Qwen, Whisper)
7.1

Custom-silicon LPU inference platform serving open models at GPU-trouncing latency via an OpenAI-compatible API.

Freemium· Free API key with rate limits; per-token paid tiers; enterprise contractslow-latency inferencevoice agents
KN

KNIME

Agents · Multi-model (OpenAI, Anthropic, Gemini, Ollama)
7.1

Visual node-based data science platform with built-in connectors for OpenAI, Anthropic, Gemini, and local LLMs.

Freemium· Free: Free · Pro: $19 / month · Team: $99 / month · Business Hub: Contact salesdata-pipelinesllm-workflows
MA

Manifest

Agents · Multi-model
7.1

Open-source LLM router that fans your agent traffic across providers and your existing AI subscriptions.

Freemium· Free: $0 /month · Pro: $19 /month · Enterprise: Let's Talkllm-routingcost-control
OM

Oh My OpenAgent

Agents · Multi-model (Claude Opus 4.7, Sonnet 4.6, GPT 5.5, Gemini 3.1 Pro)
7.1

Open-source multi-agent orchestration framework that coordinates specialized AI coders across planning, execution, and verification.

Free· Free, open-source (SUL-1.0); bring your own model API keysmulti-agent-codingautonomous-task-execution
OP

OpenArt

Image Generation · Multi-model (Sora 2, Veo 3, Kling 3.0, Seedance, GPT Image 2, Hailuo)
7.1

All-in-one AI canvas that bundles a dozen top image, video, and audio models behind a single subscription.

Freemium· Starter: $14 · Plus: $34 · Pro: $56 · Wonder: $240text-to-imagetext-to-video
PA

PandasAI

Coding · Multi-model (via LiteLLM)
7.1

Conversational data analysis library that turns natural-language questions into pandas, SQL and chart code.

Freemium· Basic: $10 · Pro: $30 · Enterprise: Contact salesdata-analysisnatural-language-sql
PO

Portkey

Agents · Multi-model
7.1

Production LLM gateway with observability, guardrails, and prompt management for teams shipping AI in anger.

Freemium· Developer: Free Forever · Production: $49/month · Enterprise: Custom Pricingllm-gatewayobservability
PF

Prompt Foundry

Evaluation · OpenAI + Anthropic (multi-model)
7.1

Prompt management and side-by-side LLM evaluation for OpenAI and Anthropic models.

Freemium· Free tier (10 prompts, 500 evals/mo); Pro $15/user/mo; Enterprise customprompt-managementmodel-comparison
RF

Respan (formerly Keywords AI)

Evaluation · Multi-model (500+ via gateway)
7.1

LLM engineering platform combining a multi-model gateway with tracing, evals, and prompt management.

Freemium· Free tier; paid plans (pricing not public); enterprise on requestllm-observabilityprompt-management
SC

Scenario

Image Generation · Multi-model (FLUX, Seedance, Kling, Hunyuan, Tripo, ElevenLabs, OpenAI, Gemini)
7.1

Custom-trained generative AI platform for studios that need on-brand image, video, 3D, and audio assets at scale.

Freemium· Starter: $15/mo · Pro: $45/mo · Max: $75/mo · Enterprise: Customcustom-lora-traininggame-asset-generation
SE

Serena

Agents · Bring your own (Claude, GPT, etc.)
7.1

Open-source MCP toolkit that gives coding agents IDE-grade symbol search, refactoring, and editing across 40+ languages.

Freemium· Core server free (MIT); optional JetBrains plugin is paid with free trialagent-codingrefactoring