denoland/deno · error · anyhow::Error

Unable to choose binary for {} Available bins: {}

Error message

Unable to choose binary for {}
  Available bins:
{}

What it means

For an npm package run via `deno x`, deno selects the `bin` entry matching the invoked command name (or the fallback name). When the package exposes multiple bins and none matches, it lists every available bin and errors instead of guessing.

Source

Thrown at cli/tools/x.rs:749

          None
        };

        if let Some(fallback_name) = fallback_name
          && let Some(exit_code) = maybe_run_local_npm_bin(
            &runner_factory,
            &runner_flags,
            runner_node_resolver,
            runner_npm_resolver,
            fallback_name.as_ref(),
            &unstable_args,
            &forwarded,
          )
          .await?
        {
          return Ok(exit_code);
        }

        Err(anyhow::anyhow!(
          "Unable to choose binary for {}\n  Available bins:\n{}",
          effective_command,
          bin_commands
            .keys()
            .map(|k| format!("    {}", k))
            .collect::<Vec<_>>()
            .join("\n")
        ))
      }
    }
    ReqRefOrUrl::Jsr(jsr_package_req_reference) => {
      let (_new_flags, new_factory) = autoinstall_package(
        ReqRef::Jsr(&jsr_package_req_reference),
        &flags,
        reload,
        command_flags.yes,
        &command_flags.ignore_scripts,
        &factory.deno_dir()?.root,

View on GitHub (pinned to 89f33cbef2)

Solutions

1. Re-run with the explicit binary from the list: `deno x some-pkg/<bin-name>`
2. Copy the spelling exactly from the 'Available bins:' section — entries are case-sensitive
3. If you maintain the package, make sure package.json's bin map includes the command name users invoke

Example fix

# before
deno x some-pkg
# after (pick a listed bin)
deno x some-pkg/some-pkg-cli

# bash: query the package's bin entries first and pass one explicitly
bins=$(npm exec --package=some-pkg -- node -p "Object.keys(require('./package.json').bin).join(' ')" 2>/dev/null)
echo "available bins: $bins"
deno x "some-pkg/$(echo $bins | awk '{print $1}')"

When it happens

Trigger: `deno x some-pkg` where some-pkg's package.json `bin` map has several entries and none matches the invoked name or the fallback.

Common situations: CLI packages that ship several executables; running the package by its name when the intended bin has a different name; case mismatches in bin names.

Related errors

• Cannot use --watch with an npm package whose bin entry is a
• Use 'deno run' to run a local file directly, 'deno x' is int
• Installation rejected
• The bench name can't be empty
• invalid doc test hashbang: #!/bin/sh (binary basename needs

AI-assisted analysis of denoland/deno@89f33cbef2 (2026-08-16). Data as JSON: /api/errors/6203c3cbb5a641fc. Report an issue: GitHub.