You can apply GitHub labels to an issue or PR by posting a comment. Labeling of issues can be very helpful for searching, tying issues together, and indicating information in a formal way, such as the status.

The Triage WG helps with labeling issues. If you are interested in helping triaging issues, see the Triage WG procedure.


The general form of the comment should be @rustbot label followed by a space-separated list of labels to add or remove. You can remove labels by prefixing them with the - character. Some examples:

  • @rustbot label A-diagnostics A-macros
  • @rustbot label +T-lang -T-compiler — Removes T-compiler and adds T-lang.

The syntax for the command is somewhat flexible, supporting a few different forms to suit your pleasure. Some examples of variants you can use:

  • @rustbot label: +T-lang, -T-compiler
  • @rustbot label: +T-lang and -T-compiler
  • @rustbot modify labels to +T-lang and -T-compiler
  • @rustbot modify labels: +T-lang and -T-compiler
  • @rustbot modify labels to +T-lang -T-compiler

The command can be terminated with a ., ;, or the end of the line.

Formally the grammar is:

Command → @rustbot modify? label-word to? :? label-list (; | .)?

label-word →
   | labels

label-list →
   | label-delta and label-list
   | label-delta , label-list
   | label-delta , and label-list

label-delta →
      + label
   | - label
   | label

label → [^.,:!?;\n() ]+


All labels can be assigned by rust-lang organization team members (and wg-triage, wg-prioritization, and wg-async). Users not on a team can only assign labels that are explicitly authorized in triagebot.toml. It is encouraged for maintainers to allow the majority of labels to be applied by anyone. An example of one that would be restricted is beta-accepted, since accepting a backport to beta is usually only done by a team member.


Labeling support is enabled on a repo by having a [relabel] table in triagebot.toml:


Permissions for allowing unauthenticated labeling is done by listing the labels in the allow-unauthenticated list:

# any label is allowed to be set by team members (anyone on a team in rust-lang/team)
# but these can be set by anyone in the world
allow-unauthenticated = [
    "C-*", # any C- prefixed label will be allowed for anyone, independent of authorization with rust-lang/team
    "!C-bug", # but not C-bug (order does not matter)


See src/handlers/