Already in a agent, please run '.exit agent' first to exit…

Error message

Already in a agent, please run '.exit agent' first to exit the current agent.

What it means

Thrown by the agent-entry function in src/config/mod.rs:1498 when an agent session is already active (`config.read().agent.is_some()`). Only one agent may be active per config at a time, so starting another requires explicitly leaving the current one first; the message tells the user the exact command to do so.

Solutions

Run `.exit agent` (or call `config.exit_agent()`) then start the new agent
Check `config.read().agent.is_some()` before entry and exit programmatically first
Refactor scripts to create a fresh session per agent instead of reusing one

Example fix

// before
config.use_agent("other-agent", None, signal).await?;
// after
if config.read().agent.is_some() {
    config.exit_agent()?;
}
config.use_agent("other-agent", None, signal).await?;

Defensive patterns

Strategy: validation

Validate before calling

if config.read().agent.is_some() {
    bail!("Already in an agent; run '.exit agent' before starting another");
}

Try / catch

if let Err(e) = config.use_agent(name, session, signal).await {
    if e.to_string().contains("Already in a agent") {
        config.exit_agent()?;
        config.use_agent(name, session, signal).await?;
    } else {
        return Err(e.into());
    }
}

Prevention

Always exit the current agent before entering a new one
Track agent-session state in your tooling and mirror exit calls
Use one session per agent in scripts rather than reusing a session

When it happens

Trigger: Running `.agent <other-name>` (or calling the entry function again) while already inside an agent session; scripts that invoke the agent command twice without exiting; nested agent switching without `.exit agent` in between.

Common situations: Users switching between agents interactively and forgetting the exit step; automation that loops over agent names reusing one session; confusion after a failed agent init left state partially set.

Understand the failure class

Background: "Invalid state transition" errors: "status must be X, actually Y", "already rejected/charging/uninstalled", "cannot ... while running" — what they mean when a library rejects your call — this error's family across 31 libraries.

Related errors

AI-assisted analysis of sigoden/aichat@82976d349a (2026-09-09). Data as JSON: /api/errors/1068b32cbb44f43d. Report an issue: GitHub.

Appendix: source

Thrown at src/config/mod.rs:1498

        }
        self.rag_template
            .as_deref()
            .unwrap_or(RAG_TEMPLATE)
            .replace("__CONTEXT__", embeddings)
            .replace("__INPUT__", text)
    }

    pub async fn use_agent(
        config: &GlobalConfig,
        agent_name: &str,
        session_name: Option<&str>,
        abort_signal: AbortSignal,
    ) -> Result<()> {
        if !config.read().function_calling {
            bail!("Please enable function calling before using the agent.");
        }
        if config.read().agent.is_some() {
            bail!("Already in a agent, please run '.exit agent' first to exit the current agent.");
        }
        let agent = Agent::init(config, agent_name, abort_signal).await?;
        let session = session_name.map(|v| v.to_string()).or_else(|| {
            if config.read().macro_flag {
                None
            } else {
                agent.agent_prelude().map(|v| v.to_string())
            }
        });
        config.write().rag = agent.rag();
        config.write().agent = Some(agent);
        if let Some(session) = session {
            config.write().use_session(Some(&session))?;
        } else {
            config.write().init_agent_shared_variables()?;
        }
        Ok(())
    }

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