Last updated: May 2026
Hermes Agent is built for developers and AI researchers who want an open foundation for local function calling and agent experiments. You build and maintain your own integrations, skills, and tools.
Vellum is built for anyone who wants a personal AI assistant that gets real work done out of the box. No coding, no command line, and no server configuration required.
Hermes Agent runs via self-hosted servers or terminal environments, with official Herald desktop apps for Mac, Windows, and Linux. Connecting messaging channels or mobile devices requires manual deployment.
Vellum works everywhere immediately. Native Mac app, iOS, Android, web app, voice, email, Slack, and Telegram, all connected to the same persistent assistant with zero server setup.
Hermes Agent gives you complete ownership of your code and local execution, but credential isolation and sandboxing depend entirely on your own host configuration.
Vellum combines local execution on your device with an isolated credential vault where keys and tokens never enter model context. You get enterprise-grade privacy defaults automatically.
Migrate everything that matters to Vellum with our import tool!
iOS app with Home Screen widgets, native Mac app, web app, voice, email, Slack, Telegram, Microsoft Teams, and Discord, now an official channel with a setup wizard. Sent messages can be edited in place in Slack and Telegram. Every surface shares the same memory and identity.
Official Herald desktop apps for macOS, Windows, and Linux with native streaming voice. Gateway routes messages across Telegram, Discord, and Slack.
Build me a habit tracker gets you a working, interactive app in the conversation. Read this page uses the browser extension to read your open tabs and act on the page you are looking at. Call the dentist and reschedule places an actual phone call with its own voice.
Executes code, custom tools, and function calls locally or on self-hosted servers. Herald desktop apps add native streaming voice, but real-world browser and mobile workflows require custom tooling.
Run on-device as a native Mac app, on Vellum's managed cloud, or self-host on your own VPS.
Run locally on desktop, self-host on a private server, or deploy via third-party community hosting like FlyHermes.
Native agent skills plus 1-click integrations with 50+ services through managed OAuth, including native Calendly and Eventbrite. Your assistant acts in real services without you touching tokens or API keys.
Manual configuration required for every connector, key, and orchestration step you want to use.
Vellum builds a structured memory of your projects, people, and preferences automatically, across every surface. It sharpens with every conversation and correction, and there is nothing to configure: no files to curate, no engine to pick, no embedding provider to wire up.
Agent-curated flat memory files with no managed persistence. Long-term memory depends on what you wire up.
Builds its own skills, learns your tone, and adapts based on what you reward and correct. Install new skills from a growing library, or just ask and it figures out a way.
Customization happens through code changes. The core agent loop itself is fixed.
Open source under MIT license. Full codebase available on GitHub.
Open source under MIT license. Full codebase available on GitHub.
Free Base plan with free credits to start. Paid plans from $30/mo (Mighty), $100 (Super), and $200 (Ultra) with pay-as-you-go credits, configurable compute and storage, and your assistant's own email and subdomain on higher tiers.
Free codebase, but you pay for infrastructure, model API usage, and ongoing maintenance to keep it running.
Run locally on Mac, in Vellum Cloud, or self-host. Vellum never has access to your data on any deployment path.
Self-hostable, but your data passes through whatever model provider you wire up. Privacy depends on your stack.
Built-in scheduling for daily briefings, weekly reports, and hourly checks that just run on a cadence.
No native scheduling. Bolt on cron or an external orchestrator.
Credentials live in an isolated vault and never enter the model layer, so prompt injection can't exfiltrate your keys. Every sensitive action asks permission with a risk badge before it runs, and guardian approvals land in one inbox.
API keys flow directly into model context for tool calls, with no isolation between credentials and LLM input.
No terminal, no API keys, no daemon. Voice-first onboarding is the default: your first experience is speaking, not configuring. Free, no credit card, up in minutes.
Herald desktop apps install in minutes on Mac and PC. Full server deployments with custom gateways and third-party managed infrastructure (FlyHermes) still require developer setup.
Vellum Cloud: 3 GB RAM and 4 GB storage by default. Mac app runs on standard Mac hardware.
Self-hosted. Resource needs scale with model size and tool load. No official minimum specs published.
Every sensitive action asks first with a risk badge, guardian approvals land in one inbox, and you can export or delete your data at any time. The trust model is written down in the docs.
Security boundaries depend entirely on your self-hosted setup. Herald added signed webhooks and A2A protocols, but host isolation and credential protection remain your responsibility.
See how every personal AI assistant stacks up across the categories that matter.
See how Vellum compares to other AI assistants easily.
Choose Vellum if you want a personal AI assistant that works out of the box across native Mac app, iOS, web app, voice, email, Telegram, and Slack, with persistent memory and managed credentials. No VPS to provision, no API keys to rotate, no terminal required. Vellum is built for every human, with native apps on every major surface and 24/7 background execution in Vellum Cloud.
Hermes Agent makes sense if you are an AI researcher or engineer building custom function-calling pipelines or testing A2A communication. With the August Herald release, it now includes native desktop apps and streaming voice. Vellum is built for users who want an assistant that works immediately across Mac, iOS, Android, Slack, and web without writing code or managing servers.
Hermes Agent is MIT licensed and free to download. Running it in production requires paying for cloud VPS hosting ($5 to $20/mo) or managed hosting like FlyHermes, plus LLM API usage. Vellum includes free cloud hosting when you sign up. Paid plans upgrade your assistant's compute and storage: Mighty at $30/mo, Super at $100/mo (plus $10 platform fee), and Ultra at $200/mo (plus $10 platform fee). For most users, all-in costs land close together, but Vellum eliminates server ops.
Vellum takes 5 to 10 minutes. Download the Mac app, sign in, and the setup wizard walks you through connecting your tools. Hermes requires provisioning a server, configuring a YAML file, and setting up API keys for each provider and integration. For non-technical users, that setup can take hours.
Vellum builds a structured, persistent memory of your work, people, and patterns automatically across every session. The assistant manages its own understanding of you, and that memory stays consistent across native Mac app, iOS, web app, voice, email, Telegram, and Slack. Hermes curates MEMORY.md and USER.md files each session, backed by SQLite, which gives you visibility into what the model knows but puts the curation burden on you.
Vellum connects to 50+ services through managed OAuth with one-click setup and no API keys to handle, including Google Workspace, Slack, Notion, GitHub, Linear, X, and Telegram. Hermes integrates via manually configured API keys and MCP servers, so each service requires its own setup and ongoing key rotation.
Vellum runs as a native Mac app, an iOS app, an Android app, and a web app, with voice, email, Telegram, Discord, and Slack surfaces in sync. Hermes Agent offers official Herald desktop apps for macOS, Windows, and Linux, plus gateway routing for Telegram, Discord, and Slack, but lacks official mobile client applications.
With Vellum, your data lives on Vellum Cloud with per-customer isolation, encryption at rest, configurable retention, and custom LLM credentials so model API keys stay under your control. Vellum never has access to your data on any deployment path, whether you run the native Mac app on your machine or use Vellum Cloud. With Hermes, your data stays on whatever server you self-host on, and uptime, backups, security patches, and credential rotation are your responsibility.
Yes. Vellum is open source and you can run it as a native Mac app on your own machine. The full Vellum experience also includes Vellum Cloud for 24/7 background execution, the OAuth credential vault, and managed infrastructure on the Pro plan from $50/mo. Either path gives you the same assistant, memory, and identity.
Technically yes. Some developers run Vellum as their daily-driver personal assistant across surfaces and use Hermes for specific technical workflows. Most people find one assistant handles everything they need. If you are unsure where to start, Vellum is the faster path to a working assistant.
Vellum is built for every human, with native Mac app, iOS, web app, voice, email, Telegram, and Slack surfaces. No terminal, no server, no API keys, and no daemon to maintain. Hermes Agent is a CLI-based framework that assumes Python, a terminal, and host administration.
