[caelaxie]

Port upstream pstack/ from f9be7aa0 (#715) through d4575673 (#724). Version goes from 0.15.27 to 0.15.28. cursor-team-kit stays 1.2.0. The short port README only changes the version.

Upstream commits

Verified with git log f9be7aa0..main -- pstack cursor-team-kit on https://github.com/cursor/plugins:

• 6b78e9f4 / #721 — fix(pstack): TLA+ default and no-verifier fallback in create-formal-verification-skill
• 7b353f78 / #716 — add maintain-formal-verification-skill (new skill, plus edits to create-formal-verification-skill, poteto-help, guide verify-and-ship section and guide page 9)
• d4575673 / #724 — bump to 0.15.28, sync guide page 6 with create-formal-verification-skill

cursor-team-kit/ has no commits after f9be7aa0. No .cursor-plugin/plugin.json (same as earlier port PRs). README skill-table lines from upstream are not applied. This port's README has no skill table.

Grok adaptations

New upstream text is copied verbatim, except:

• Root plugin.json is bumped to 0.15.28. Upstream's .cursor-plugin/plugin.json bump is not copied. This port has no Cursor plugin manifest.
• The short port README version line is bumped to 0.15.28.

Touched files already carried these adaptations, and this port leaves them in place:

• docs/guide/06-verify-and-ship.md keeps .grok/skills/verify-<app>/ where upstream says .cursor/skills/verify-<app>/.
• docs/guide/09-make-it-yours.md keeps .grok/skills/<your-name>-mode/SKILL.md and Grok Build's /create-skill where upstream says .cursor and Cursor's built-in create-skill.
• skills/poteto-help/SKILL.md keeps the existing Grok Build paragraph in place of upstream's "Other tools can read the skills… spawn Cursor subagents…" paragraph. The Claude Code install paragraph stays, because docs/harness/claude-code.md is already in this port. Existing wording stays: ~/.grok/rules/pstack-models.md, spawn_subagent, subagent_type: "pstack:poteto-agent", isolation: "worktree", bundled deslop / control-cli / control-ui, and no custom mode.

skills/create-formal-verification-skill/SKILL.md, skills/maintain-formal-verification-skill/SKILL.md, and skills/poteto-help/references/recipes.md match upstream. The new skill has no .cursor paths and no spawn wording to adapt.

CI

Validate plugin succeeded on 6574fb4. It reported Validated 59 skills, 2 agents, and 23 playbooks and Ran 68 tests across 5 files.

Harness proof

grok 1.0.62, on cursor/port-pstack-0.15.28-e85e at 6574fb4e491c15da161f3c6931be194cd2df1aa5. Full output: #7 (comment)

$ grok plugin install https://github.com/pstack-ports/grok-pstack@cursor/port-pstack-0.15.28-e85e --trust
Installed 1 plugin(s) from https://github.com/pstack-ports/grok-pstack@cursor/port-pstack-0.15.28-e85e: pstack

$ grok plugin list --json
[
  {
    "status": "installed",
    "name": "pstack",
    "repo_key": "grok-pstack-619a4a2c",
    "version": "0.15.28",
    "path": "/home/ubuntu/.grok/installed-plugins/grok-pstack-619a4a2c",
    "source": "https://github.com/pstack-ports/grok-pstack",
    "marketplace": null
  }
]

$ git -C ~/.grok/installed-plugins/grok-pstack-619a4a2c rev-parse HEAD
6574fb4e491c15da161f3c6931be194cd2df1aa5

grok inspect loads create-formal-verification-skill and maintain-formal-verification-skill from that plugin (userInvocable: true). The installed create-formal-verification-skill says TLA+ is the default for a bad order of events in any language, and if no verifier runs on the language, say so and test the real code with generated inputs. The installed poteto-help lines mention /maintain-formal-verification-skill when covered code changed after the recorded sync commit, in the skill table, and in references/recipes.md.

A model turn did not run. grok -p '/maintain-formal-verification-skill' --max-turns 1 --cwd /tmp --verbatim exited 1: not signed in, and XAI_API_KEY is unset.

  

[caelaxie]

verdict: changes requested (comment review, same account as author).

diff is clean. checked against upstream d4575673 (still pstack head):

• create-formal-verification-skill, maintain-formal-verification-skill, poteto-help/references/recipes.md: byte-identical to upstream.
• poteto-help/SKILL.md, guide 06, guide 09: only the pre-existing grok adaptations differ; new upstream lines land verbatim, including the 09 anchor fix.
• plugin.json + README at 0.15.28, matches upstream .cursor-plugin/plugin.json. cursor-team-kit stays 1.2.0, no upstream commits since.
• validate plugin: green. no open issue to link, so no Closes/Refs needed.

blocking: harness proof is "pending". need, on head 6574fb4:

1. grok plugin install <path> --trust and grok plugin list showing pstack 0.15.28.
2. changed skills exercised: maintain-formal-verification-skill present and loadable in the installed copy, plus the new create-formal-verification-skill and poteto-help text visible there. a live /maintain-formal-verification-skill turn if auth allows; if only cli auth blocks it, install+list plus inspect/installed-copy output is enough for this text-only change.

add it to the body or as a comment and i'll merge.

[cursor]

Harness proof for head 6574fb4e491c15da161f3c6931be194cd2df1aa5 on cursor/port-pstack-0.15.28-e85e. grok 1.0.62, installed the same way as .github/workflows/ci.yml (https://x.ai/cli/stable resolved to 1.0.62, then curl -fsSL https://x.ai/cli/install.sh | bash -s 1.0.62).

$ grok --version
grok 1.0.62 (1474f9cbdd91)

$ grok plugin install https://github.com/pstack-ports/grok-pstack@cursor/port-pstack-0.15.28-e85e --trust
Installed 1 plugin(s) from https://github.com/pstack-ports/grok-pstack@cursor/port-pstack-0.15.28-e85e: pstack

$ grok plugin list
  grok-pstack-619a4a2c: pstack [git: https://github.com/pstack-ports/grok-pstack]

$ grok plugin list --json
[
  {
    "status": "installed",
    "name": "pstack",
    "repo_key": "grok-pstack-619a4a2c",
    "version": "0.15.28",
    "path": "/home/ubuntu/.grok/installed-plugins/grok-pstack-619a4a2c",
    "source": "https://github.com/pstack-ports/grok-pstack",
    "marketplace": null
  }
]

$ grok plugin details pstack
grok-pstack-619a4a2c
  path: /home/ubuntu/.grok/installed-plugins/grok-pstack-619a4a2c
  kind: git: https://github.com/pstack-ports/grok-pstack
  installed: 2026-10-20T01:25:49.626197742+00:00
  updated: 2026-10-20T01:25:49.626197742+00:00
  plugins (1):
    pstack v0.15.28
  description: if you want to go fast, go deep first. pstack helps you write less, but higher quality code. rigorous agent workflows you can parallelize with confidence.
  components: 1 skill dir(s), 0 command dir(s), 1 agent dir(s)

$ git -C ~/.grok/installed-plugins/grok-pstack-619a4a2c rev-parse HEAD
6574fb4e491c15da161f3c6931be194cd2df1aa5

grok plugin list --json and grok plugin details show pstack 0.15.28. The installed git checkout is branch cursor/port-pstack-0.15.28-e85e at head 6574fb4. The plain grok plugin list line does not print the version.

grok inspect loads maintain-formal-verification-skill and create-formal-verification-skill from that plugin (userInvocable: true). 59 skills from plugin pstack.

  Skills (59)
  └ create-formal-verification-skill                    plugin: pstack
  └ maintain-formal-verification-skill                  plugin: pstack
  └ poteto-help                                         plugin: pstack

$ grok inspect --json | jq -r '.skills[] | select(.name=="maintain-formal-verification-skill" or .name=="create-formal-verification-skill" or .name=="poteto-help") | "\(.name)\tplugin=\(.source.plugin_name)\tuserInvocable=\(.userInvocable)\t\(.description)"'
create-formal-verification-skill	plugin=pstack	userInvocable=true	Generate a project-local skill that formally verifies the code where a bug costs the most and tests reach the least, in any language, with whichever verification tool fits. Use for /create-formal-verification-skill, "model-check this race", "prove this invariant", or when concurrency, retries, state machines, parsers, or unsafe code need more than tests.
maintain-formal-verification-skill	plugin=pstack	userInvocable=true	Bring a project's formal verification back in line with the code after the code changes: find the commits that touched verified code, update the model, harness, or properties to describe the code as it is now, rerun, and say whether each failure is drift in the verification or a bug in the code. Use for /maintain-formal-verification-skill, "is the model still true to the code", or after merges and refactors that touched verified code without rechecking it.
poteto-help	plugin=pstack	userInvocable=true	Guides users through pstack setup, /poteto-mode, and picking the skill, playbook, or principle for a task. Type /poteto-help with a question.

Installed path: /home/ubuntu/.grok/installed-plugins/grok-pstack-619a4a2c (HEAD 6574fb4).

create-formal-verification-skill (skills/create-formal-verification-skill/SKILL.md), TLA+ default and the no-verifier guidance, from the installed copy:

Pick the tool that answers the question at the lowest cost: a model checker, a proof assistant, an SMT-backed verifier, or another tool. Whether events can happen in a bad order usually suits a model checker over a small model of the design, and TLA+ is the default for that in any language. Whether the code itself behaves for every input, as with memory safety, overflow, or a data-structure invariant, usually suits a verifier that runs on the code. If no verifier runs on this language, say so, and test the real code with generated inputs, not a hand model of the function. A property that must hold at every size, where a bound is not enough, can need a proof. Prefer a tool that the repo's developers can install and run, and tell the user why you chose it.

poteto-help new lines, from the installed copy.

skills/poteto-help/SKILL.md:

- No formal verification skill in the project means no property is checked past what tests reach. Mention `/create-formal-verification-skill` when the question is about a race, an invariant, or another case tests rarely hit. When one exists and the code it covers changed after the commit it records as last in sync, mention `/maintain-formal-verification-skill` if the question touches that code.

| Bring a formal verification back in line after the code it covers changed, and learn whether a failure is drift or a bug | [`/maintain-formal-verification-skill`](../maintain-formal-verification-skill/SKILL.md) |

skills/poteto-help/references/recipes.md:

- `/create-formal-verification-skill prove <property> holds in <module>, even when <steps> interleave or retry.` After merges or refactors in that code: `/maintain-formal-verification-skill`.

A model turn did not run. grok -p '/maintain-formal-verification-skill' --max-turns 1 --cwd /tmp --verbatim exited 1: not signed in, and XAI_API_KEY is unset.

[caelaxie]

portreview: approved at 6574fb4.

The harness proof in #7 (comment) (grok 1.0.62) closes the earlier gap:

• grok plugin install …@cursor/port-pstack-0.15.28-e85e --trust installed pstack
• grok plugin list --json and grok plugin details pstack show pstack 0.15.28
• the installed checkout rev-parse HEAD is 6574fb4e491c15da161f3c6931be194cd2df1aa5, which is the PR head
• grok inspect loads create-formal-verification-skill, maintain-formal-verification-skill and poteto-help from plugin pstack (userInvocable: true), and the installed text includes the TLA+ default, the no-verifier fallback, and the new poteto-help and recipes lines
• no live turn ran because the CLI is not signed in. As in #5 and #6, inspect loading the changed skills counts as exercise.

Content was already checked against upstream d4575673. Validate plugin passed on 6574fb4. Squash-merging now, pinned to 6574fb4.