What causes "Mochat channel requires the `channel-mochat` feature" in zeroclaw-labs/zeroclaw?

Rebuild with cargo build --release --features channel-mochat

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

Mochat channel requires the `channel-mochat` feature

Error message

Mochat channel requires the `channel-mochat` feature

What it means

Raised by build_channel_by_id when channel_id = "mochat" is requested but the binary was compiled without the `channel-mochat` feature. The enabled arm builds the Mochat channel with peer_resolver and a poll_interval_secs from [channels.mochat]; without the feature only the bail arm exists.

Source

Thrown at crates/zeroclaw-channels/src/orchestrator/mod.rs:9602

                .get("default")
                .context("Mochat channel is not configured")?;
            let alias = "default".to_string();
            let peer_resolver: Arc<dyn Fn() -> Vec<String> + Send + Sync> = {
                let cfg_arc = config_arc.clone();
                let alias = alias.clone();
                Arc::new(move || cfg_arc.read().channel_external_peers("mochat", &alias))
            };
            Ok(Arc::new(MochatChannel::new(
                mc.api_url.clone(),
                mc.api_token.clone(),
                alias,
                peer_resolver,
                mc.poll_interval_secs,
            )))
        }
        #[cfg(not(feature = "channel-mochat"))]
        "mochat" => {
            anyhow::bail!("Mochat channel requires the `channel-mochat` feature");
        }
        #[cfg(feature = "channel-imessage")]
        "imessage" => {
            if !config.channels.imessage.contains_key("default") {
                anyhow::bail!("iMessage channel is not configured");
            }
            let alias = "default".to_string();
            let peer_resolver: Arc<dyn Fn() -> Vec<String> + Send + Sync> = {
                let cfg_arc = config_arc.clone();
                let alias = alias.clone();
                Arc::new(move || cfg_arc.read().channel_external_peers("imessage", &alias))
            };
            Ok(Arc::new(IMessageChannel::new(alias, peer_resolver)))
        }
        #[cfg(not(feature = "channel-imessage"))]
        "imessage" => {
            anyhow::bail!("iMessage channel requires the `channel-imessage` feature");
        }

View on GitHub (pinned to 88bb9c8533)

Solutions

Rebuild with cargo build --release --features channel-mochat
Or use --features channels-full
Or remove [channels.mochat] and "mochat" bindings
Check zeroclaw_channels::listing::is_channel_type_compiled("mochat")

Example fix

# before
 cargo build --release

 # after
 cargo build --release --features channel-mochat

Defensive patterns

Strategy: validation

Validate before calling

use zeroclaw_channels::listing::is_channel_type_compiled;

if !is_channel_type_compiled("mochat") {
    eprintln!("rebuild with --features channel-mochat or remove [channels.mochat]");
}

Type guard

fn mochat_available() -> bool {
    zeroclaw_channels::listing::is_channel_type_compiled("mochat")
}

Try / catch

match build_channel_by_id(&config_arc, "mochat") {
    Ok(ch) => { /* use */ }
    Err(e) if e.to_string().contains("requires the `channel-mochat` feature") => {
        // skip; rebuild hint
    }
    Err(e) => return Err(e),
}

Prevention

Mochat is cfg-gated only; adding it to a build is zero-dep cost, so consider channels-full for WeChat-adjacent stacks
Lint config channel ids against the compiled listing on deploy

When it happens

Trigger: start_channels / build_channel_by_id selecting "mochat" from an [channels.mochat] block or agent binding in a build lacking --features channel-mochat.

Common situations: Default-feature builds (mochat is in channels-full only); WeChat-adjacent stacks where Mochat was configured but the binary was compiled from a curated feature list; configs synced between full and slim deployments.

Related errors

AI-assisted analysis of zeroclaw-labs/zeroclaw@88bb9c8533 (2026-08-23). Data as JSON: /api/errors/c4b22a25238ea9a3. Report an issue: GitHub.