guardian review session could not clear MCP servers: {err}

Error message

guardian review session could not clear MCP servers: {err}

What it means

Error "guardian review session could not clear MCP servers: {err}" thrown in openai/codex.

Source

Thrown at codex-rs/core/src/guardian/review_session.rs:1422

    ));
    guardian_config.base_instructions_provenance = Some(BaseInstructionsProvenance::Custom);
    guardian_config.notify = None;
    guardian_config.developer_instructions = None;
    guardian_config.permissions.approval_policy = Constrained::allow_only(AskForApproval::Never);
    let guardian_permission_profile =
        read_only_guardian_permission_profile(parent_config.permissions.permission_profile());
    guardian_config
        .permissions
        .set_permission_profile(guardian_permission_profile)
        .map_err(|err| {
            anyhow::anyhow!("guardian review session could not set permission profile: {err}")
        })?;
    guardian_config.include_apps_instructions = false;
    guardian_config
        .mcp_servers
        .set(HashMap::new())
        .map_err(|err| {
            anyhow::anyhow!("guardian review session could not clear MCP servers: {err}")
        })?;
    if let Some(live_network_config) = live_network_config
        && guardian_config.permissions.network.is_some()
    {
        let network_constraints = guardian_config
            .config_layer_stack
            .requirements()
            .network
            .as_ref()
            .map(|network| network.value.clone());
        guardian_config.permissions.network = Some(NetworkProxySpec::from_config_and_constraints(
            live_network_config,
            network_constraints,
            guardian_config.permissions.permission_profile(),
        )?);
    }
    for feature in [
        Feature::Collab,

View on GitHub (pinned to 339751715c)

Solutions

Investigate why clearing MCP servers on the review session failed; see the reported error.

When it happens

Trigger: Thrown at codex-rs/core/src/guardian/review_session.rs:1422 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/01cc89b2dbdd347e. Report an issue: GitHub.