Update stack skill docs

Author: RhysSullivan

.agents/skills/stack/SKILL.md

@@ -40,8 +40,9 @@ can restore the previous branch tips, PR bases, and stack metadata.
 - `stack status`: show the relevant tracked stack graph and include open PR details when GitHub is available.
 - `stack guide`: print the opinionated happy path for agents and humans.
 - `stack track <branch> --onto <parent>`: record stack intent for an existing branch.
-- `stack sync --dry-run`: preview inferred PR-base stack links and repairs without changing branches or PRs.
-- `stack sync`: infer clear PR-base stack links, repair descendants, retarget PRs, and refresh stack blocks.
+- `stack sync --dry-run [branch]`: preview inferred PR-base stack links and repairs without changing branches or PRs.
+- `stack sync [branch]`: infer clear PR-base stack links, repair descendants, retarget PRs, and refresh stack blocks. With a branch argument, sync only the stack containing that branch.
+- `stack sync --continue-on-failure` / `stack sync --keep-going`: process independent stacks, summarize successes and failures, and exit nonzero if any stack failed.
 - `stack doctor`: inspect local Git, GitHub, stack metadata, trunk branches, and undo journal health without changing anything.
 - `stack merge [branch]`: dry-run root PR merge plus descendant repair.
 - `stack merge [branch] --apply`: retarget immediate child PRs, squash-merge the root PR, then repair descendants.
@@ -58,6 +59,8 @@ gh pr create --base dev --head stack-a
 gh pr create --base stack-a --head stack-b
 stack sync --dry-run
 stack sync
+stack sync cleanup/schema-source
+stack sync --keep-going
 ```
 
 Prefer this workflow. `stack sync --dry-run` should show the inferred links, and
@@ -112,6 +115,17 @@ changed, or the repo needs the safe common maintenance flow. It:
 Run `stack sync --dry-run` first when you want a preview of inferred links and
 repairs before mutation.
 
+`stack sync <branch>` scopes sync to the stack containing that branch. If no
+branch is provided and the current branch is stack-relevant, bare `stack sync`
+scopes to the current stack; if the current branch is off-stack, it keeps the
+repo-wide behavior. `--dry-run` follows the same scoping rules.
+
+Use `stack sync --continue-on-failure` or `stack sync --keep-going` when one
+independent stack should not block the rest. It runs each root stack separately,
+prints succeeded and failed stacks, preserves the usual failure cleanup block for
+each failed stack, saves undo information for every mutated stack, and exits
+nonzero if any stack failed.
+
 Sync output is intentionally outcome-oriented. It should show the stack tree with
 icons like `●`, `✓`, `◌`, and `✕`, plus changed PRs/backups/undo instructions. It
 should not default to internal phase logs like fetch, inspect, or reconcile.

skills-lock.json

@@ -5,7 +5,7 @@
       "source": "kitlangton/stack",
       "sourceType": "github",
       "skillPath": "skills/stack/SKILL.md",
-      "computedHash": "a2e9d48c0d0aab5cb208464423a686877d46c5df9ed6740352c6d96feebefc30"
+      "computedHash": "e0e92c2ec925a19225f075de3703b7e05b4185ccea1a6d36621b825c582a99f3"
     }
   }
 }