What does bring your own agent mean?
It means you supply the coding agent through an existing subscription or API key, while another product supplies the environment, compute, publishing or collaboration layer.
Grain / Learn / Bring your own agent: what BYO pricing means
Definition
Bring your own agent: what BYO pricing means
Bring your own agent means the workspace or infrastructure does not require you to buy its coding model as part of the product. You keep a separate agent subscription or key, choose the agent that does the work and pay the other tool for the place where work runs, persists or gets shared.
Definition
BYO pricing separates two bills that bundled builders combine. The agent bill covers model access or an agent subscription. The workspace bill covers some combination of compute, storage, publishing, data and collaboration. Separation matters because tokens are not the same resource as a durable app. A long reasoning session may consume significant model usage and produce a tiny static page. A simple prompt may produce an application that needs months of hosting and data. With a bring-your-own-agent product, changing the model does not require moving the workspace, and changing the workspace does not necessarily replace the agent. The tradeoff is that you select, authorize and understand both parts instead of receiving one integrated experience.
Subtypes
| Commercial model | Agent cost | Workspace cost | Model choice | Best fit |
|---|---|---|---|---|
| Bundled agent and hosting | Included credits or usage within the product | Included or metered by the same vendor | Limited to the vendor's supported agent | People who want one prompt-to-hosted-app experience |
| BYO subscription | Existing monthly agent plan | Separate workspace, compute or publishing plan | Agents accepted by the workspace | People already using a preferred coding agent every day |
| BYO API key | Metered directly by the model provider | Separate infrastructure usage or subscription | Models accepted by the application | Teams that want usage control and programmatic routing |
| Self-hosted BYO | Existing subscription or API usage | Your infrastructure and operations | Whatever the self-hosted system supports | Teams prioritizing infrastructure control |
What to check before choosing
- Define the billing boundary. Ask whether agent tokens, remote compute, storage, published traffic, databases and team seats are separate meters. A low workspace fee can still sit beside a large model bill.
- Check subscription acceptance. Some products accept an existing agent login, while others require an API key. These are both BYO models, but their economics and authentication steps differ.
- Confirm actual agent portability. A broad protocol such as MCP helps tools connect, but the workflow can still depend on vendor-specific files, prompts or runtime assumptions. Test with the agent you intend to use.
- Measure inactive cost. Development environments, always-on workspaces and published static artifacts have different idle costs. Pay for the state that must remain, not merely the session that created it.
- Plan the fallback. Confirm that ordinary files can leave the workspace and that changing agents does not make existing artifacts unreadable. Portability is stronger when output is not trapped inside a proprietary conversation.
Examples
| Example | Model verified on 2026-09-04 | Pricing shape | Criterion it illustrates |
|---|---|---|---|
| Replit Agent | Own agent bundled with browser development and hosting | Free and paid tiers include tier-scaled agent credits, with deployment resources handled in the same ecosystem | One vendor owns the building and hosting experience |
| CloudCLI | Bring an existing Claude Code, Cursor, Codex or Gemini CLI subscription or key | Paid environment subscription, with higher tiers adding environments and team features | The remote development environment is sold separately from the agent |
| Coder | Run supported coding agents inside self-hosted workspaces | Free Community tier, with paid tiers priced per user but not publicly numbered | The organization supplies infrastructure and the agent |
| Grain | Bring an existing CLI coding agent | Free publishing and limited workspace capacity, with paid always-on compute and team features | The durable artifact layer is separate from model usage |
Worked example: a developer already has a coding-agent subscription and needs to publish a customer-support triage tool. Under a bundled model, the developer prompts the builder inside its browser product and consumes that vendor's agent credits, even though another agent plan is already paid for. Hosting and app services then remain in that same product. Under a BYO model, the developer keeps the preferred agent, creates the project locally or in a remote environment and pays a separate product only for the workspace or publishing layer. In Grain, the concrete sequence is to download the Mac app, sign in with grain login, run grain init, let the agent write the tool, then use grain push, grain checkpoint -m 'support triage' and grain share --public. The result is a share URL shaped like https://<slug>.share.rungrain.com. To compare honestly, total the existing agent plan, any API overage, workspace compute, required team seats and the lifetime of the published tool. The BYO path wins only if agent choice and separated billing are worth managing two product boundaries.
Where Grain sits
Grain is bring-your-own-agent by design. It does not generate code or sell model tokens. Its grain init command creates a workspace for the current folder and writes agent configuration for supported CLI agents; any CLI agent that speaks MCP can work with the product. The free tier includes the Mac app, CLI, unlimited published artifacts, ten sleeping sandboxes and one always-on workspace. Pro is $65 per user per month and adds more always-on workspaces, team seats, shared spaces and custom domains. This model fits someone who already pays for a coding agent and wants output to keep a URL, files, optional Postgres, logins, schedules and sharing. It does not fit someone seeking a single vendor to choose the model, generate the app and host it from one browser prompt. A bundled builder such as Replit Agent is the clearer choice for that reader.
Frequently asked questions
Is bring your own agent cheaper?
It can be cheaper when you already pay for an agent and do not want a second token markup. Compare the complete bill, including model use, compute, storage, databases and seats.
Does BYO agent mean I can use any model?
No. It means the agent is supplied separately. The workspace still has a supported protocol, client list and authentication method, so test the exact agent you plan to use.
What is the difference between BYO agent and BYO key?
A BYO subscription can reuse access from an agent product you already pay for. A BYO API key usually bills model usage directly by consumption. A tool may support one or both.
When is a bundled agent better?
Choose a bundle when you want one vendor to supply the model, building interface and hosting, and the simplicity matters more than keeping your current agent or separating the bills.
Keep your agent and publish its work
Download the free Mac app and use the coding-agent plan you already have.
Free forever. No card. Bring your own agent.
Sources · facts verified 2026-09-04
- Replit pricing · 2026-09-04
- CloudCLI pricing · 2026-09-04
- Coder pricing · 2026-09-04