openai/codex · error · std::io::Error

duplicate agent role name `{role_name}` declared in config

Error message

duplicate agent role name `{role_name}` declared in config

What it means

Error "duplicate agent role name `{role_name}` declared in config" thrown in openai/codex.

Source

Thrown at codex-rs/core/src/config/agent_roles.rs:133

fn push_agent_role_warning(startup_warnings: &mut Vec<String>, err: std::io::Error) {
    let message = format!("Ignoring malformed agent role definition: {err}");
    tracing::warn!("{message}");
    startup_warnings.push(message);
}

async fn load_agent_roles_without_layers(
    fs: &dyn ExecutorFileSystem,
    cfg: &ConfigToml,
) -> std::io::Result<BTreeMap<String, AgentRoleConfig>> {
    let mut roles = BTreeMap::new();
    if let Some(agents_toml) = cfg.agents.as_ref() {
        for (declared_role_name, role_toml) in &agents_toml.roles {
            let (role_name, role) = read_declared_role(fs, declared_role_name, role_toml).await?;
            validate_required_agent_role_description(&role_name, role.description.as_deref())?;

            if roles.insert(role_name.clone(), role).is_some() {
                return Err(std::io::Error::new(
                    std::io::ErrorKind::InvalidInput,
                    format!("duplicate agent role name `{role_name}` declared in config"),
                ));
            }
        }
    }

    Ok(roles)
}

async fn read_declared_role(
    fs: &dyn ExecutorFileSystem,
    declared_role_name: &str,
    role_toml: &AgentRoleToml,
) -> std::io::Result<(String, AgentRoleConfig)> {
    let mut role = agent_role_config_from_toml(fs, declared_role_name, role_toml).await?;
    let mut role_name = declared_role_name.to_string();
    if let Some(config_file) = role.config_file.as_deref() {

View on GitHub (pinned to 339751715c)

Solutions

1. Rename or remove one of the duplicated agent roles across the config layers.

When it happens

Trigger: Thrown at codex-rs/core/src/config/agent_roles.rs:133 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of openai/codex@339751715c (2026-08-25). Data as JSON: /api/errors/0bb270386ab6ec79. Report an issue: GitHub.