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+---
+name: start-sprint
+description: >
+  Start sprint work on a team branch. Use when the user says "start sprint",
+  "start working on the server/client", "begin sprint", or invokes /start-sprint.
+  Merges main into the team branch, finds the active sprint, reads the sprint
+  briefing, and presents the work plan with ticket details.
+user-invocable: true
+allowed-tools: Bash, Read, Grep, Glob
+---
+
+# Start Sprint Skill
+
+Prepare a team branch for sprint work: sync with main, load the sprint
+briefing, and present actionable next steps.
+
+## Workflow
+
+### 1. Determine the team branch
+
+If the user provided a branch name as argument, use it. Otherwise use the
+current branch (`git branch --show-current`). Valid team branches: `server`,
+`client`.
+
+If on `main`, ask the user which team branch to start.
+
+### 2. Sync the branch
+
+```bash
+git fetch --all
+git checkout <branch>
+git merge origin/main --no-edit
+```
+
+If the merge has conflicts, report them and stop — do not force-resolve.
+
+### 3. Find the active sprint
+
+```bash
+db/connectors/ticket sprint --active
+```
+
+Extract the sprint ID and name from the JSON output. If no active sprint,
+report that and stop.
+
+### 4. Read the sprint briefing
+
+Read `docs/sprints/sprint-N/<team>.md` where N is the sprint ID and team
+matches the branch name. If the branch is `server` or `client`, use that
+directly. For other branches, check if a matching briefing exists.
+
+Also check for a `joint.md` briefing — joint tasks involve both teams and
+should be mentioned.
+
+### 5. Load ticket details
+
+For each ticket listed in the briefing, run:
+```bash
+db/connectors/ticket show <id>
+```
+
+Identify which tickets are actionable now (no open blockers) vs blocked.
+
+### 6. Read key decisions
+
+Read the decision files referenced in the sprint briefing so the agent has
+full architectural context before starting work.
+
+### 7. Present the work plan
+
+Output a summary:
+- Sprint name and goal
+- Branch status (clean merge or conflicts)
+- Actionable tickets (unblocked, ready to start)
+- Blocked tickets (and what blocks them)
+- Key decisions loaded
+- Suggested first task (lowest ID unblocked ticket)
+
+Then mark the first actionable ticket as `in_progress`:
+```bash
+db/connectors/ticket status <id> in_progress
+```