| name | system-information |
| description | Resolve which dependency versions are actually installed, from composer show and composer.lock, when diagnosing version-specific behavior such as a method, argument or class that does not exist in the release that is really running. For the PHP runtime itself (version, OS, loaded extensions) use the php-environment-check skill instead. |
System Information
Use this skill when a problem might depend on the installed dependency versions
rather than the code: a bug that looks like a version mismatch, a method, argument, or
class that does not exist in the release that is actually installed.
Capabilities
| Need | Use |
|---|
| PHP version, OS, OS family, loaded extensions | php-environment-check skill |
| Installed version of a package | composer show <vendor/package> |
| Installed versions of a family of packages | composer show '<vendor>/<prefix>*' |
| Authoritative record of every installed version | composer.lock (packages / packages-dev) |
The php-environment-check skill reports the runtime only, it does not return
package versions. Use Composer for those.
Resolving package versions
composer.json declares constraints (what is allowed); composer.lock records what is
actually installed. For "what is really running", trust the lock, not the constraint.
- One package:
composer show symfony/console → installed version plus details.
- A family:
composer show 'symfony/ai-*' → every matching package and its version.
- Machine-readable:
composer show --format=json symfony/console.
- No Composer binary, or you want the raw record: look the package up by
name under
packages in composer.lock and read its version field, but do not load the whole lock
file into context.
Monorepo / path-repo note: locally linked packages (for example symlinked symfony/ai-*
in this repository) report dev-main or a path reference instead of a semver tag, and that
is the working copy, not a released version.
Diagnosing a version mismatch
- Identify the package behind the failing API; the namespace usually maps to it
(
Symfony\Component\Console\… → symfony/console).
- Read the installed version with
composer show <package> (or from composer.lock).
- Compare it against the version the code expects: a method or argument added in a newer
minor, or removed/renamed in a newer major, is the classic signature.
- Report the gap precisely: name the package, the installed version, and the required
one: "symfony/console is 6.4 (installed), but the code calls a 7.1 API."
Rules
- Reach for
composer show first; it is cheaper and more structured than reading
composer.lock wholesale.
- Report only the one or two facts that change the diagnosis (e.g. "symfony/console is
6.4, the code uses a 7.1 API"), never the entire lock file.
- Never run state-changing commands.
composer show is read-only; composer require,
composer update, and composer install are not. This skill is read-only inspection.
