affaan-m/ECC · error · anyhow::Error

Configured harness runner for {runner_key} is missing a prog

Error message

Configured harness runner for {runner_key} is missing a program

What it means

The agent_program function resolves the executable path for a given agent type. If a harness runner is configured for the runner_key but its program field is empty after trimming, the configuration is incomplete and the system cannot spawn the agent. This catches misconfigured runner entries before attempting to spawn.

Source

Thrown at ecc2/src/session/manager.rs:2335

            session.state
        );
    }

    if let Some(worktree) = session.worktree.as_ref() {
        let _ = crate::worktree::remove(worktree);
    }

    db.delete_session(&session.id)?;
    Ok(())
}

fn agent_program(cfg: &Config, agent_type: &str) -> Result<PathBuf> {
    let harness = HarnessKind::from_agent_type(agent_type);
    let runner_key = SessionHarnessInfo::runner_key(agent_type);
    if let Some(runner) = cfg.harness_runner(&runner_key) {
        let program = runner.program.trim();
        if program.is_empty() {
            anyhow::bail!("Configured harness runner for {runner_key} is missing a program");
        }
        return Ok(PathBuf::from(program));
    }

    match harness {
        HarnessKind::Claude => Ok(PathBuf::from("claude")),
        HarnessKind::Codex => Ok(PathBuf::from("codex")),
        HarnessKind::OpenCode => Ok(PathBuf::from("opencode")),
        HarnessKind::Gemini => Ok(PathBuf::from("gemini")),
        other => anyhow::bail!("Unsupported agent type: {other}"),
    }
}

fn resolve_session(db: &StateStore, id: &str) -> Result<Session> {
    let session = if id == "latest" {
        db.get_latest_session()?
    } else {
        db.get_session(id)?

View on GitHub (pinned to 01e15490f0)

Solutions

Set the program field in the harness runner config to the full path of the agent executable (e.g., '/usr/local/bin/claude')
Verify the agent binary is installed and accessible at the configured path
Remove the runner entry if you want to use the default program resolution (claude, codex, opencode, gemini from PATH)
Validate config on startup — check that every configured runner has a non-empty program

Example fix

// before (config):
// harness_runners:
//   claude-runner:
//     program: ""

// after (config):
// harness_runners:
//   claude-runner:
//     program: "/usr/local/bin/claude"
// or remove the entry entirely to use PATH-based defaults

Defensive patterns

Strategy: validation

Validate before calling

fn validate_runner_config(cfg: &Config) -> Result<()> {
    for (key, runner) in cfg.list_harness_runners() {
        if runner.program.trim().is_empty() {
            anyhow::bail!("harness runner '{key}' has empty program");
        }
    }
    Ok(())
}

Prevention

Validate all harness runner configs on startup before any session is launched
Use config schema validation to reject empty program fields at load time
Test agent_program resolution during health checks

When it happens

Trigger: A harness_runner entry exists in config for the runner_key (derived from agent type) but the program field is empty or whitespace-only.

Common situations: Config file has a runner entry with a missing or blank 'program' key. Environment variable interpolation for the program path resolved to empty. Copy-paste config error where the program value was accidentally deleted.

Related errors

AI-assisted analysis of affaan-m/ECC@01e15490f0 (2026-08-13). Data as JSON: /api/errors/c47897b8594acac6. Report an issue: GitHub.