What Sets Them Apart
The architectural foundation reveals each project's priorities. Symphony is built on Elixir and the Erlang OTP platform, leveraging fault-tolerant supervision trees and lightweight BEAM processes designed for telecom-grade reliability. Each coding agent runs as a supervised process that automatically restarts on failure without affecting peers. Agent Orchestrator is maintained under AgentWrapper as a local TypeScript control plane for coordinating coding-agent sessions, routing feedback, and keeping the human operator in the pull-request loop.
Symphony and Agent Orchestrator at a Glance
Workflow initiation follows opposite models. Symphony operates as a background daemon that continuously polls issue trackers — currently Linear — for new work items, automatically spawning coding agents when tickets appear. This pull-based model means Symphony runs autonomously without developer intervention once configured. Agent Orchestrator uses a push-based model initiated by the ao start command, which reads the codebase and backlog to decompose work into parallelizable tasks on demand.
Agent isolation strategies differ in granularity. Symphony assigns one agent per issue with a dedicated working directory, git branch, and context window, following a strict lifecycle from Todo through In Progress, Human Review, Merging, to Done. Agent Orchestrator creates isolated git worktrees for parallel coding-agent sessions, using branch/workspace separation and feedback routing so CI failures, review comments, and merge conflicts return to the right session before humans merge the work.
CI integration reveals different maturity levels. Agent Orchestrator has deep CI awareness — when a build fails, it injects failure logs directly into the relevant agent session for autonomous fixing, and when code review comments arrive, it routes them to the appropriate agent with full context. Symphony generates proof-of-work artifacts before landing code but relies on the standard PR review process rather than autonomous CI remediation.
Supervision and Fault Tolerance Models
The supervision and fault tolerance models reflect their language ecosystems. Symphony's OTP supervisors provide automatic crash recovery with configurable restart strategies, hot code reloading for updating orchestration logic without stopping agents, and built-in distributed computing support for multi-node deployments. Agent Orchestrator relies on JavaScript's event loop and plugin architecture for reliability, with process monitoring handled at the application level.
Scalability characteristics favor different team sizes. Agent Orchestrator is designed for practical parallelism on a local workstation or team-controlled machine, with isolated git worktrees reducing file conflicts while CI capacity, disk, model budgets, and API-rate limits set real-world ceilings. Symphony's BEAM VM is designed for massive concurrency with thousands of lightweight processes, but its current implementation focuses on one-agent-per-issue rather than fine-grained task decomposition within a single feature.
Integration ecosystem breadth differs significantly. Agent Orchestrator's current source story is adapter breadth rather than inherited Composio integrations: it supports terminal-agent adapters such as Claude Code, Codex, Cursor, Aider, Goose, GitHub Copilot, and OpenCode, runs through tmux on Darwin/Linux and ConPTY on Windows, and connects work back to GitHub-style pull-request feedback loops. Symphony currently supports Linear-driven issue workflows in the prototype, with an architecture designed for extension but a narrower public integration surface today.
Community and Project Maturity
Community and project maturity show different trajectories. Agent Orchestrator now sits in the AgentWrapper/agent-orchestrator repository with 8K+ GitHub stars, an Apache-2.0 license, and recent source activity; treat older self-bootstrapping and exact line-count claims as historical lore unless a current source reconfirms the numbers. Symphony has 14,700+ GitHub stars backed by OpenAI's brand but is explicitly labeled as prototype software with a recommendation to implement your own hardened version based on its SPEC.md document.
The self-improvement angle sets Agent Orchestrator apart. Because the orchestrator itself is an AI agent, it can reason about task decomposition strategies, learn from merge conflict patterns, and adapt its routing decisions based on agent performance. Symphony follows a more traditional daemon model where the orchestration logic is deterministic code, with AI limited to the individual coding agents rather than the coordination layer.
The Bottom Line
Choose Symphony if you want a daemon-based workflow that autonomously processes issue tracker tickets with fault-tolerant OTP supervision and you are comfortable extending a prototype. Choose Agent Orchestrator if you need maximum parallelism, autonomous CI remediation, plugin extensibility, and a platform that treats orchestration itself as an AI-driven decision process. For production use today, Agent Orchestrator is more feature-complete; for architectural elegance and scalability potential, Symphony's Elixir foundation offers a stronger long-term bet.