# FAQ // :toc: // Set toclevels to be at least your hugo [markup.tableOfContents.endLevel] config key :toclevels: 4 == What is Updatecli? A command line tool that applies update strategies described in a manifest. The manifest declares what to update, where, and under which conditions; Updatecli reads it and does the work. It needs no server and no database (the manifest and the files it updates are the only state). The link:/docs/prologue/introduction/["Introduction" page] covers the model in full. == Is Updatecli pull or push based? Both, in sequence. Each pipeline pulls a value from somewhere (a registry, a Git repository, an API), checks the conditions you declared, and only then writes that value where it belongs. == What is the difference between `diff` and `apply`? `updatecli pipeline diff`:: Reports what *would* change. Targets run in dry-run mode, and committing and pushing are switched off. `updatecli pipeline apply`:: Applies the changes, then commits, pushes, and opens the action you declared. Use `--commit=false` or `--push=false` to stop short of either. NOTE: The bare `updatecli diff` and `updatecli apply` forms still work but are deprecated in favour of the `pipeline` subcommands. See the link:/docs/help/deprecations/["Deprecations" page]. == Does `diff` ever change anything on disk? Almost never (but there is one exception worth knowing). A `shell` target runs your command in both modes. Updatecli cannot know what a script does, so it exports `DRY_RUN=true` and leaves the decision to the script. A script that ignores `DRY_RUN` will write during a `diff`. TIP: Guard the write with `if test "$DRY_RUN" == "false"`. The link:/docs/plugins/resource/shell/["Shell" page] shows the full pattern. == Do I need a GitHub token, and which variable holds it? Anything that reads from GitHub needs a token, and anything that writes needs one with write access. Updatecli looks in this order: . `spec.token` in the manifest . `UPDATECLI_GITHUB_TOKEN` (with `UPDATECLI_GITHUB_USERNAME`) . the GitHub App variables . `GITHUB_TOKEN` The link:/docs/help/environment/["Environment variables" page] lists all of them. If you get `no access token found`, see the link:/docs/help/troubleshooting/["Troubleshooting" page]. == Why did the run finish cleanly but open no pull request? Usually because nothing needed changing, which is the expected outcome most of the time. The other common causes are a condition that did not pass, `--commit=false` or `--push=false`, or a filter such as `--pipeline-ids` narrowing the run. Run again with `--debug` to see which. The link:/docs/help/troubleshooting/#_nothing_happened["Nothing happened" section] walks through each case. == Why does Updatecli seem to hang? Most likely it is waiting out a GitHub rate limit rather than hanging. When the limit is reached Updatecli retries, then sleeps until the window resets, logging: [source,text] ---- GitHub API rate limit reached, on hold for 45 minute(s) until 2026-07-30 11:15:00 UTC. The process will resume automatically. ---- See link:/docs/help/troubleshooting/#_rate_limiting["Rate limiting"]. == Am I hitting a Docker Hub rate limit? Docker Hub limits how many manifests you may pull, and an unauthenticated run burns through that allowance quickly. The link:/docs/help/docker_hub_rate_limit/["Docker Hub rate limit" page] explains the limits and how to stay under them. == Can I run several Updatecli instances in parallel? Yes, but pass `--unique-tmp-dir`. By default every instance shares `$TMPDIR/updatecli`, so two runs cloning the same repository will fight over the same directory. The flag gives each run its own. == Where does Updatecli write temporary files? Under `$TMPDIR/updatecli`, with `bin/` and `report/` beneath it. `--clean` removes the directory at the end of a run. == Go Further * link:/docs/help/troubleshooting/[Troubleshooting] - error messages, what causes them, and what to do. * link:/docs/help/environment/[Environment variables] - every variable Updatecli reads. * link:/docs/help/deprecations/[Deprecations] - what changed and how to migrate. * link:/support/[Support] - community channels, and how to report a bug.