What causes "No patterns provided to file_glob" in warpdotdev/warp?

Validate patterns non-empty before dispatching the action and reject with a descriptive tool error

No patterns provided to file_glob

Error message

No patterns provided to file_glob

What it means

run_file_glob rejects an empty patterns vector up front: file_glob (v1 or v2) with zero patterns is treated as a malformed invocation rather than matching everything.

Source

Thrown at app/src/ai/blocklist/action_model/execute/file_glob.rs:206

        self.active_session
            .as_ref(ctx)
            .session(ctx)
            .is_some_and(|session| session.supports_parallel_command_execution())
    }
}

fn is_file_glob_v2(input: &ExecuteActionInput) -> bool {
    matches!(input.action.action, AIAgentActionType::FileGlobV2 { .. })
}

async fn run_file_glob(
    patterns: Vec<String>,
    absolute_path: String,
    session: Option<Arc<Session>>,
    shell_launch_data: Option<ShellLaunchData>,
) -> anyhow::Result<FileGlobV2Result> {
    if patterns.is_empty() {
        return Err(anyhow::anyhow!("No patterns provided to file_glob"));
    }
    let Some(session) = session else {
        return Err(anyhow::anyhow!("No session provided to file_glob"));
    };
    let shell_type = session.shell().shell_type();

    let is_in_git_repo = is_git_repository(&absolute_path, session.as_ref())
        .await
        .unwrap_or_else(|e| {
            report_error!(e.context("Failed to run command to check if in git repository"));
            false
        });

    if is_in_git_repo {
        run_git_ls_files_command(
            &patterns,
            &absolute_path,
            session.as_ref(),

View on GitHub (pinned to e72fd7aacb)

Solutions

Validate patterns non-empty before dispatching the action and reject with a descriptive tool error
If the model intended 'everything', translate empty patterns into an explicit '**/*' at the tool boundary
Log the raw action payload when this fires to catch schema/deserialization bugs

Example fix

// before
ActionExecution::new_async(async move {
    run_file_glob(patterns_clone, absolute_path, session, shell_launch_data).await
});

// after
if patterns.is_empty() {
    return Err(anyhow!("file_glob requires at least one pattern"));
}
ActionExecution::new_async(async move {
    run_file_glob(patterns_clone, absolute_path, session, shell_launch_data).await
});

Defensive patterns

Strategy: validation

Validate before calling

if patterns.is_empty() {
    return Err(anyhow!("file_glob requires at least one pattern"));
}

Type guard

fn valid_glob_request(patterns: &[String]) -> bool {
    !patterns.is_empty()
}

Try / catch

match run_file_glob(patterns, path, session, shell).await {
    Err(e) if e.to_string() == "No patterns provided to file_glob" => {
        Err(anyhow!("model emitted an empty pattern list; re-prompt"))
    }
    r => r,
}

Prevention

Validate the action payload schema (minItems on patterns) at deserialization
Return a descriptive tool error to the model so it re-issues the call with patterns
Decide explicitly whether empty patterns mean 'reject' or '**/*' and enforce it at one boundary

When it happens

Trigger: The agent model emits a FileGlob action whose patterns list is empty, or a caller filters/validates patterns into nothing before invoking run_file_glob (file_glob.rs:212-214).

Common situations: Model outputs an empty array for patterns; upstream validation strips invalid entries leaving none; deserialization of the action payload defaults to an empty vec.

Related errors

AI-assisted analysis of warpdotdev/warp@e72fd7aacb (2026-08-16). Data as JSON: /api/errors/0a504c4673ead6a1. Report an issue: GitHub.