Sandstorm — MCP Tools Reference

Sandstorm manages isolated Docker agent stacks. Each stack is a full clone of the project repo with its own containers, ports, and an inner Claude agent.

IMPORTANT: Always use the MCP tools (mcp__sandstorm-tools__*) to manage stacks. Never use CLI commands (sandstorm up, sandstorm task, etc.) directly — the MCP tools go through the Electron app's control plane, which tracks stacks in the database and keeps the UI in sync.

Available MCP Tools

Critical Rules

• NEVER set branch to main. Omit the branch parameter — it defaults to the stack name, which becomes a feature branch. Setting branch: "main" causes pushes to go directly to main, bypassing code review. This has caused loss of work.
• NEVER tear down stacks unless the user explicitly asks. No inference, no cleanup, no "let me tear this down first." The ONLY valid trigger is the user directly requesting teardown.
• Always create PRs after pushing. Use .sandstorm/scripts/create-pr.sh to open a pull request from the feature branch.
• NEVER rewrite, summarize, or embellish ticket text when dispatching. Pass the ticket body verbatim. See the "Verbatim Ticket Dispatch" section below.

Workflows

Spec quality gate (mandatory for tickets)

Before calling create_stack or dispatch_task for a ticket:

1. Fetch the ticket body using the project's fetch-ticket script:

   bash
   1.sandstorm/scripts/fetch-ticket.sh <N>

   If the script doesn't exist, warn the user: "No fetch-ticket script configured. Run sandstorm init to set up a ticket provider."
2. Read the project's .sandstorm/spec-quality-gate.md
3. Evaluate each criterion — PASS or FAIL
4. If any FAIL → present specific gaps to the user, enter a refinement loop (do NOT dispatch)
5. If all PASS → show your assumptions list, ask the user to approve
6. On approval → call create_stack with gateApproved: true

If you skip this step, the backend will reject the call with GATE_CHECK_REQUIRED and you will need to run the gate check anyway. Always run it proactively.

If the user explicitly says to skip the gate (e.g., "just start it", "skip the gate"), use forceBypass: true instead.

Typical flow: ticket to PR

1. Run spec quality gate (see above) — required before dispatch
2. create_stack — name, projectDir, ticket, gateApproved: true (do NOT pass branch — it defaults to the stack name)
3. dispatch_task — pass the verbatim ticket body as the task prompt (see Verbatim Ticket Dispatch below)
4. get_task_status — check when done
5. get_diff — review changes
6. push_stack — commit and push to the feature branch
7. Create a pull request:

   bash
   1.sandstorm/scripts/create-pr.sh --title "Fix auth token expiry" --body "Fixes #28"

Do NOT tear down stacks — only the user decides when to tear down.

Verbatim Ticket Dispatch

When the user says "start issue #N", "spin up a stack for issue #N", or any variation:

1. Fetch the full ticket body using the project's fetch-ticket script:

   bash
   1.sandstorm/scripts/fetch-ticket.sh <N>

2. Pass the ticket body verbatim as the task parameter to create_stack or dispatch_task
3. Do NOT summarize, rewrite, add implementation details, or "improve" the ticket text
4. Never add file paths, class names, or implementation steps that aren't in the ticket

If the user gives verbal instructions that differ from the ticket, update the ticket first using the project's update-ticket script:

bash
1.sandstorm/scripts/update-ticket.sh <N> "<updated body>"

Then fetch and dispatch the updated body. The ticket is the single source of truth.

Why this matters:

• The inner Claude has full repo context — it can figure out implementation details itself
• The inner Claude reads CLAUDE.md, understands the codebase, and makes appropriate decisions
• Adding implementation specifics from the outer Claude constrains the inner Claude and can steer it wrong
• Summarizing loses important details and nuance from the original ticket

Create stack and dispatch work (for a ticket)

bash
1# 1. Fetch the ticket body verbatim
2TICKET_BODY=$(.sandstorm/scripts/fetch-ticket.sh 28)
3
4# 2. Create stack with the unmodified ticket body as the task
5mcp__sandstorm-tools__create_stack({
6  name: "issue-28-fix-auth-bug",
7  projectDir: "/path/to/project",
8  ticket: "28",
9  gateApproved: true,
10  task: <TICKET_BODY — the full, unmodified ticket text>
11})

NEVER pass branch: "main". Omit the branch parameter entirely.

The task parameter dispatches work immediately after creation — no need to call dispatch_task separately.

Monitor and iterate

mcp__sandstorm-tools__get_task_status({ stackId: "issue-28-fix-auth-bug" })
mcp__sandstorm-tools__get_task_output({ stackId: "issue-28-fix-auth-bug" })
mcp__sandstorm-tools__get_diff({ stackId: "issue-28-fix-auth-bug" })
mcp__sandstorm-tools__dispatch_task({ stackId: "issue-28-fix-auth-bug", prompt: "Looks good but add limit/offset params" })

Review, push, create PR

bash
1mcp__sandstorm-tools__get_diff({ stackId: "issue-28-fix-auth-bug" })
2mcp__sandstorm-tools__push_stack({ stackId: "issue-28-fix-auth-bug", message: "Fix auth token expiry with user-facing error" })
3.sandstorm/scripts/create-pr.sh --title "Fix auth token expiry" --body "Fixes #28"

Tool Details

create_stack

The stack builds in the background. Use get_task_status or list_stacks to check when it's ready.

dispatch_task

Write goal-oriented prompts. Describe WHAT to achieve, not HOW. The inner Claude has the full repo context.

When dispatching for a ticket: Pass the ticket body verbatim. Do not summarize, rewrite, or add implementation details.

For follow-up tasks (not initial ticket dispatch): goal-oriented prompts are fine.

Good follow-up: "Looks good but add limit/offset params to the list endpoint"

Bad initial dispatch: Rewriting "Fix auth bug" into "Open src/auth.ts, find line 42, change the catch block..."

get_task_status

Returns the current task state for a stack: running, completed, failed, or idle.

get_task_output

get_diff

Returns the full git diff of uncommitted changes in the stack's workspace. Always review before pushing.

get_logs

push_stack

teardown_stack

Stops containers, removes workspace, archives stack to history. This is irreversible. Always check for unpushed changes first with get_diff.

Important Rules

• Use MCP tools only. Never bypass with raw sandstorm CLI commands or docker commands.
• No polling loops. Run get_task_status as a one-shot check when the user asks. Never write sleep/poll loops.
• Review before pushing. Always get_diff before push_stack.
• Check before teardown. Always get_diff before teardown_stack to avoid losing work.
• Verbatim ticket dispatch. When dispatching work for a ticket, pass the ticket body verbatim as the task prompt. Never summarize, rewrite, add file paths, class names, or implementation steps that aren't in the ticket. If the user's instructions differ from the ticket, update the ticket first, then dispatch.
• Stacks appear in the UI. Because MCP tools go through the Electron control plane, every stack you create will be visible in the Sandstorm Desktop UI.
• NEVER use main as the branch. Omit the branch parameter so stacks always work on feature branches.
• NEVER tear down stacks unless the user explicitly requests it. No automatic cleanup.
• Always create PRs. After push_stack, use .sandstorm/scripts/create-pr.sh to open a pull request.
• Spec quality gate. Always run /spec-check before dispatching work for a ticket. The backend enforces this — calls without gateApproved: true will be rejected with GATE_CHECK_REQUIRED.