nikivdev/code · error

resolver {} returned empty output for {}

Error message

resolver {} returned empty output for {}

What it means

A resolver command may exit successfully but produce no stdout; since the resolver's stdout is the selected session/candidate, an empty result is unusable and the tool bails naming the resolver and candidate. This guards against silently proceeding with an empty selection.

Source

Thrown at src/ai.rs:12598

            .current_dir(target_path)
            .output()
            .with_context(|| format!("failed to run resolver {}", resolver.name))?;
        if !output.status.success() {
            let stderr = String::from_utf8_lossy(&output.stderr).trim().to_string();
            bail!(
                "resolver {} failed for {}: {}",
                resolver.name,
                candidate,
                if stderr.is_empty() {
                    format!("exit status {}", output.status)
                } else {
                    stderr
                }
            );
        }
        let stdout = String::from_utf8_lossy(&output.stdout).trim().to_string();
        if stdout.is_empty() {
            bail!(
                "resolver {} returned empty output for {}",
                resolver.name,
                candidate
            );
        }

        return Ok(Some(CodexResolvedReference {
            name: resolver
                .inject_as
                .clone()
                .unwrap_or_else(|| resolver.name.clone()),
            source: "resolver".to_string(),
            matched: candidate.clone(),
            command: Some(command_text),
            output: compact_codex_context_block(&stdout, 12, 1200),
        }));
    }

View on GitHub (pinned to a747e741ae)

Solutions

1. Ensure the resolver prints the selected candidate to stdout
2. Fix the resolver script to emit the value (not stderr) and exit 0 only with output
3. Verify the input fed to the resolver is non-empty before invoking

Example fix

// before
pick | grep -i foo >/dev/null
// after
printf '%s\n' "$pick" | grep -i foo | head -1

let out = Command::new(&program).args(&rest).current_dir(&dir).output()?;
let stdout = String::from_utf8_lossy(&out.stdout).trim().to_string();
if !out.status.success() || stdout.is_empty() {
    eprintln!("resolver '{}' produced no usable output", resolver.name);
}

fn resolver_output_ok(out: &std::process::Output) -> bool {
    out.status.success() && !String::from_utf8_lossy(&out.stdout).trim().is_empty()
}

When it happens

Trigger: Resolver exits 0 but prints nothing: the picker was fed no input lines, a filter matched nothing and the script swallows the exit code, or the script writes results to stderr instead of stdout.

Common situations: Resolver script piping an empty session list into fzf; scripts that `echo` diagnostics but forget to print the selection; quoting bugs redirecting the selection to the wrong stream.

Related errors

• gen returned no output
• empty resolver command for {}
• resolver {} failed for {}: {}
• kimi returned empty output
• Lin.app is not running

AI-assisted analysis of nikivdev/code@a747e741ae (2026-09-01). Data as JSON: /api/errors/0569bbe2e20a6b53. Report an issue: GitHub.