zeroclaw-labs/zeroclaw · error · anyhow::Error

browser.backend='auto' found no usable backend (agent-browse

Error message

browser.backend='auto' found no usable backend (agent-browser missing, rust-native unavailable, computer-use sidecar unreachable)

What it means

Error "browser.backend='auto' found no usable backend (agent-browser missing, rust-native unavailable, computer-use sidecar unreachable)" thrown in zeroclaw-labs/zeroclaw.

Source

Thrown at crates/zeroclaw-tools/src/browser.rs:419

                    return Ok(ResolvedBackend::RustNative);
                }
                if Self::is_agent_browser_available().await {
                    return Ok(ResolvedBackend::AgentBrowser);
                }

                let computer_use_err = match self.computer_use_available() {
                    Ok(true) => return Ok(ResolvedBackend::ComputerUse),
                    Ok(false) => None,
                    Err(err) => Some(err.to_string()),
                };

                if Self::rust_native_compiled() {
                    if let Some(err) = computer_use_err {
                        anyhow::bail!(
                            "browser.backend='auto' found no usable backend (agent-browser missing, rust-native unavailable, computer-use invalid: {err})"
                        );
                    }
                    anyhow::bail!(
                        "browser.backend='auto' found no usable backend (agent-browser missing, rust-native unavailable, computer-use sidecar unreachable)"
                    )
                }

                if let Some(err) = computer_use_err {
                    anyhow::bail!(
                        "browser.backend='auto' needs agent-browser CLI, browser-native, or valid computer-use sidecar (error: {err})"
                    );
                }

                anyhow::bail!(
                    "browser.backend='auto' needs agent-browser CLI, browser-native, or computer-use sidecar"
                )
            }
        }
    }

    /// Validate URL against allowlist

View on GitHub (pinned to 88bb9c8533)

Solutions

1. Install agent-browser, enable browser-native, or start the computer-use sidecar; then retry.

When it happens

Trigger: Thrown at crates/zeroclaw-tools/src/browser.rs:419 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of zeroclaw-labs/zeroclaw@88bb9c8533 (2026-08-23). Data as JSON: /api/errors/01e8d962cd336e32. Report an issue: GitHub.