Version 2.1 implemented a round of significant changes to how things work in Agent OS. Here is a summary of what's new in version 2.1.0:

TL;DR

Here's the brief overview. It's all detailed below and the docs are updated to reflect all of this.

• Option to leverage Claude Code's new "Skills" feature for reading standards
• Option to enable or disable delegating to Claude Code subagents
• Replaced "single/multi-agent modes" with more flexible configuration options
• Retired the short-lived "roles" system. Too complex, and better handled with standard tooling (more below).
• Removed documentation & verification bloat
• Went from 4 to 6 more specific development phases (use 'em all or pick and choose!):
  1. plan-product -- (no change) Plan your product's mission & roadmap
  2. shape-spec -- For shaping and planning a feature before writing it up
  3. write-spec -- For writing your spec.md
  4. create-tasks -- For creating your tasks.md
  5. implement-tasks -- Simple single-agent implementation of tasks.md
  6. orchestrate-tasks -- For more advanced, fine-grain control and multi-agent orchestration of tasks.md.
• Simplified & improved project upgrade script

Let's unpack these updates in detail:

Claude Code Skills support

2.1 adds official support for Claude Code Skills.

When the config option standards_as_claude_code_skills is true, this will convert all of your standards into Claude Code Skills and not inject references to those Standards like Agent OS normally would.

2.1 also provides a Claude Code command, improve-skills which you definitely should run after installing Agent OS in your project with the skills option turned on. This command is designed to improve and rewrite each of your Claude Code Skills descriptions to make them more useable and discoverable by Claude Code.

Enable/Disable delegation to Claude Code subagents

2.1 introduces an config option to enable or disable delegating tasks to Claude Code subagents. You can disable subagents by setting use_claude_code_subagents to false.

When set to false, and when using Claude Code, you can still run Agent OS commands in Claude Code, and instead of delegating most tasks to subagents, Claude Code's main agent will execute everything.

While you lose some context efficiency of using subagents, you can token efficiency and some speed gains without the use of subagents.

Replaced "single-agent & multi-agent modes" with new config options

2.0.x had introduced the concepts of multi-agent and single-agent modes, where multi-agent mode was designed for using Claude Code with subagents. This naming and configuration design proved suboptimal and inflexible, so 2.1.0 does away with the terms "single-agent mode" and "multi-agent mode".

Now we configure Agent OS using these boolean options in your base ~/agent-os/config.yml:

claude_code_commands: true/false use_claude_code_subagents: true/false agent_os_commands: true/false

The benefits of this new configuration approach are:

• Now you can use Agent OS with Claude Code with or without delegating to subagents. (subagents bring many benefits like context efficiency, but also come with some tradeoffs—higher token usage, less transparency, slower to finish tasks).

• Before, when you had both single-agent and multi-agent modes enabled, your project's agent-os/commands/ folder ended up with "multi-agent/" and "single-agent/" subfolders for each command, which is confusing and clumsy to use. Now in 2.1.0, your project's agent-os/commands/ folder will not have these additional "modes" subfolders.

• Easier to integrate additional feature configurations as they become available, so that you can mix and match the exact set of features that fit your preferred coding tools and workflow style. For example, we're also introducing an option to make use of the new Claude Code Skills feature (or you can opt out). More on this below.

Retired (short-lived) "Roles" system

2.0.x had introduced a concept of "Roles", where your roles/implementers.yml and roles/verifiers.yml contained convoluted lists of agents that could be assigned to implement tasks. It also had a script for adding additional "roles".

All of that is removed in 2.1.0. That system added no real benefit over simply using available tooling (like Claude Code's own subagent generator) for spinning up your subagents.

2.1.0 introduces an 'orchestrate-tasks' phase, which achieves the same thing that the old "Roles" system intended: Advanced orchestration of multiple specialized subagents to carry out a complex implementation. More on this below.

Removed documentation & verification bloat

2.0.x had introduced a bunch of "bloat" that quickly proved unnecessary and inefficient. These bits have been removed in 2.1.0:

• Verification of your spec (although the spec-verifier Claude Code subagent is still available for you to call on, if/when you want)
• Documentation of every task's implementation
• Specialized verifiers (backend-verifier, frontend-verifier)

The final overall verification step for a spec's implementation remains intact.

From 4 to 6 more specific development phases

While some users use all of Agent OS' workflow for everything, many have been picking the parts they find useful and discarding those that don't fit their workflow—AS THEY SHOULD!

2.1.0 establishes this as a core principle of Agent OS: You can use as much or as little of it as you want!

With that in mind, we've moved from 4 to 6 different phases of development that can potentially be powered by Agent OS:

1. plan-product -- No changes here. This is for establishing your product's mission, roadmap and tech-stack.

2. shape-spec -- Use this when you need to take your rough idea for a feature and shape it into a well-scoped and strategized plan, before officially writing it up. This is where the agent asks you clarifying questions and ends up producing your requirements.md.

• Already got your requirements shaped? Skip this and drop those right into your spec's requirements.md 👍

3. write-spec -- Takes your requirements.md and formalizes it into a clear and concise spec.md.

4. create-tasks -- Takes your spec.md and breaks it down into a tasks list, grouped, prioritized and ready for implementation.

5. implement-tasks -- Just want to build right now(!), then use this to implement your tasks.md with your main agent.

6. orchestrate-tasks -- Got a big complex feature and want to orchestrate multiple agents, with more fine-grain control over their contexts? Use this. It provides a structure to delegate your task groups to any Claude Code subagents you've created. Or if you're not using Claude Code, it generates targeted prompt files (as was established in 2.0.x).

Simplified & improved project upgrade script

Now whenever you need to upgrade your Agent OS project installation (to a new version or to push configuration changes or standards changes to a project), now when you run project-install.sh or project-update.sh, the system will:

• Check and compare your incoming version & configs to your current project's
• Show you what will stay intact or be removed & re-installed
• Ask you to confirm to proceed.