Output format·Data Science & ML

marimo Notebook

Name: marimo Notebook
Author: marimo-team

Write a marimo notebook in a Python file in the right format.

You say

Buy it · $29 Read it before you buy $29 Written by marimo-team · unverified publisher

Context cost: 9.5k tokensestimated from the bundle, loaded when it triggers
Bundle: 14 files · 38.1 kBtext throughout, nothing executable
Licence: Apache-2.0paid listing
Last change: —no release on file
Servers it uses: Noneruns standalone

What it does

Write a marimo notebook in a Python file in the right format.

Installed, it changes the agent in these ways.

What this skill changes about the agent is not written down here yet. The listing was collected from its source, and the description is in its own SKILL.md.

Output format

Produces one artefact, exactly shaped.

marimonotebookspython

Filed under

Data Science & ML

The skill itself

This is the whole product. A skill is instructions the model reads, so there is nothing behind the listing you cannot see first — the front matter loads with every session, and the body below it loads when the skill triggers.

SKILL.md8.3 kB · 283 lines

--- name: marimo-notebook description: Write a marimo notebook in a Python file in the right format. ---

6# Notes for marimo Notebooks

8marimo uses Python to create notebooks, unlike Jupyter which uses JSON. Here's an example notebook:

10```python

11# /// script

12# dependencies = [

13# "marimo",

14# "numpy==2.4.3",

15# ]

16# requires-python = ">=3.14"

17# ///

19import marimo

21__generated_with = "0.20.4"

22app = marimo.App(width="medium")

25@app.cell

26def _():

27 import marimo as mo

28 import numpy as np

30 return mo, np

33@app.cell

34def _():

35 print("hello world")

36 return

39@app.cell

40def _(np, slider):

41 np.array([1,2,3]) + slider.value

42 return

45@app.cell

46def _(mo):

47 slider = mo.ui.slider(1, 10, 1, label="number to add")

48 slider

49 return (slider,)

52@app.cell

53def _():

54 return

57if __name__ == "__main__":

58 app.run()

60```

62Notice how the notebook is structured with functions can represent cell contents. Each cell is defined with the @app.cell decorator and the inputs/outputs of the function are the inputs/outputs of the cell. marimo usually takes care of the dependencies between cells automatically.

64## Running Marimo Notebooks

66```bash

67# Run as script (non-interactive, for testing)

68uv run <notebook.py>

70# Run interactively in browser

71uv run marimo run <notebook.py>

73# Edit interactively

74uv run marimo edit <notebook.py>

75```

77## Script Mode Detection

79Use mo.app_meta().mode == "script" to detect CLI vs interactive:

81```python

82@app.cell

83def _(mo):

84 is_script_mode = mo.app_meta().mode == "script"

85 return (is_script_mode,)

86```

88## Key Principle: Keep It Simple

90**Show all UI elements always.** Only change the data source in script mode.

92- Sliders, buttons, widgets should always be created and displayed

93- In script mode, just use synthetic/default data instead of waiting for user input

94- Don't wrap everything in if not is_script_mode conditionals

95- Don't use try/except for normal control flow

97### Good Pattern

99```python

100# Always show the widget

101@app.cell

102def _(ScatterWidget, mo):

103 scatter_widget = mo.ui.anywidget(ScatterWidget())

104 scatter_widget

105 return (scatter_widget,)

106

107# Only change data source based on mode

108@app.cell

109def _(is_script_mode, make_moons, scatter_widget, np, torch):

110 if is_script_mode:

111 # Use synthetic data for testing

112 X, y = make_moons(n_samples=200, noise=0.2)

113 X_data = torch.tensor(X, dtype=torch.float32)

114 y_data = torch.tensor(y)

115 data_error = None

116 else:

117 # Use widget data in interactive mode

118 X, y = scatter_widget.widget.data_as_X_y

119 # ... process data ...

120 return X_data, y_data, data_error

121

122# Always show sliders - use their .value in both modes

123@app.cell

124def _(mo):

125 lr_slider = mo.ui.slider(start=0.001, stop=0.1, value=0.01)

126 lr_slider

127 return (lr_slider,)

128

129# Auto-run in script mode, wait for button in interactive

130@app.cell

131def _(is_script_mode, train_button, lr_slider, run_training, X_data, y_data):

132 if is_script_mode:

133 # Auto-run with slider defaults

134 results = run_training(X_data, y_data, lr=lr_slider.value)

135 else:

136 # Wait for button click

137 if train_button.value:

138 results = run_training(X_data, y_data, lr=lr_slider.value)

139 return (results,)

140```

141

142## State and Reactivity

143

144Variables between cells define the reactivity of the notebook for 99% of the use-cases out there. No special state management needed. Don't mutate objects across cells (e.g., my_list.append()); create new objects instead. Avoid mo.state() unless you need bidirectional UI sync or accumulated callback state. See [STATE.md](references/STATE.md) for details.

145

146## Don't Guard Cells with if Statements

147

148Marimo's reactivity means cells only run when their dependencies are ready. Don't add unnecessary guards:

149

150```python

151# BAD - the if statement prevents the chart from showing

152@app.cell

153def _(plt, training_results):

154 if training_results: # WRONG - don't do this

155 fig, ax = plt.subplots()

156 ax.plot(training_results['losses'])

157 fig

158 return

159

160# GOOD - let marimo handle the dependency

161@app.cell

162def _(plt, training_results):

163 fig, ax = plt.subplots()

164 ax.plot(training_results['losses'])

165 fig

166 return

167```

168

169The cell won't run until training_results has a value anyway.

170

171## Don't Use try/except for Control Flow

172

173Don't wrap code in try/except blocks unless you're handling a specific, expected exception. Let errors surface naturally.

174

175```python

176# BAD - hiding errors behind try/except

177@app.cell

178def _(scatter_widget, np, torch):

179 try:

180 X, y = scatter_widget.widget.data_as_X_y

181 X = np.array(X, dtype=np.float32)

182 # ...

183 except Exception as e:

184 return None, None, f"Error: {e}"

185

186# GOOD - let it fail if something is wrong

187@app.cell

188def _(scatter_widget, np, torch):

189 X, y = scatter_widget.widget.data_as_X_y

190 X = np.array(X, dtype=np.float32)

191 # ...

192```

193

194Only use try/except when:

195- You're handling a specific, known exception type

196- The exception is expected in normal operation (e.g., file not found)

197- You have a meaningful recovery action

198

199## Cell Output Rendering

200

201Marimo only renders the **final expression** of a cell. Indented or conditional expressions won't render:

202

203```python

204# BAD - indented expression won't render

205@app.cell

206def _(mo, condition):

207 if condition:

208 mo.md("This won't show!") # WRONG - indented

209 return

210

211# GOOD - final expression renders

212@app.cell

213def _(mo, condition):

214 result = mo.md("Shown!") if condition else mo.md("Also shown!")

215 result # This renders because it's the final expression

216 return

217```

218

219## PEP 723 Dependencies

220

221Notebooks created via marimo edit --sandbox have these dependencies added to the top of the file automatically but it is a good practice to make sure these exist when creating a notebook too:

222

223```python

224# /// script

225# requires-python = ">=3.12"

226# dependencies = [

227# "marimo",

228# "torch>=2.0.0",

229# ]

230# ///

231```

232

233## marimo check

234

235When working on a notebook it is important to check if the notebook can run. That's why marimo provides a check command that acts as a linter to find common mistakes.

236

237```bash

238uvx marimo check <notebook.py>

239```

240

241Make sure these are checked before handing a notebook back to the user.

242

243**Important**: you have a tendency to over-do variables with an underscore prefix. You should only apply this to one or two variables at most. Consider creating a new variable instead of prefixing entire cells in marimo.

244

245## api docs

246

247If the user specifically wants you to use a marimo function, you can locally check the docs via:

248

249```

250uv --with marimo run python -c "import marimo as mo; help(mo.ui.form)"

251```

252

253## tests

254

255By default, marimo discovers and executes tests inside your notebook.

256When the optional pytest dependency is present, marimo runs pytest on cells that

257consist exclusively of test code - i.e. functions whose names start with test_.

258If the user asks you to add tests, make sure to add the pytest dependency is added and that

259there is a cell that contains only test code.

260

261For more information on testing with pytest see [PYTEST.md](references/PYTEST.md)

262

263Once tests are added, you can run pytest from the commandline on the notebook to run pytest.

264

265```

266pytest <notebook.py>

267```

268

269## Additional resources

270

271- For marimo notebooks that run in width=columns [SQL.md](references/COLUMNS.md)

272- For SQL use in marimo see [SQL.md](references/SQL.md)

273- For UI elements in marimo [UI.md](references/UI.md)

274- For exposing functions/classes as top level imports [TOP-LEVEL-IMPORTS.md](references/TOP-LEVEL-IMPORTS.md)

275- For exporting notebooks (PDF, HTML, markdown, etc.) [EXPORTS.md](references/EXPORTS.md)

276- For state management and reactivity [STATE.md](references/STATE.md)

277- For deployment of marimo notebooks [DEPLOYMENT.md](references/DEPLOYMENT.md)

278- For custom interactive widgets with anywidget [ANYWIDGET.md](references/ANYWIDGET.md)

279- For external editing and --watch mode [WATCHING.md](references/WATCHING.md)

280- For expensive notebooks (caching, lazy eval, mo.stop) [EXPENSIVE.md](references/EXPENSIVE.md)

281- For configuration (pyproject.toml, marimo.toml) [CONFIGURATION.md](references/CONFIGURATION.md)

282- For reactivity model (DAG, variable scoping, mutations) [REACTIVITY.md](references/REACTIVITY.md)

283

In the file

SKILL.md1,119 words

Files14

LicenceApache-2.0

Why you can read it

Nothing in a skill executes. The client loads the text and the model follows it, so a skill can be audited the way a runbook is — by reading it.

What it costs in context

Skills are not billed by the call. They are paid for in context: every token the instructions occupy is a token your code, your diff and your conversation cannot use. Here is what this one takes and when it takes it.

≈30

always loaded

The name and description, so the model knows the skill exists and when to reach for it.

9,495

on trigger

The instruction body and 13 supporting files, read only when the skill fires.

4.8%

of a 200k window

Ten skills this size would take about 48% of the window before you open a file.

050k100k150k200k context window

9.5k tokens, estimated from the bundle at four bytes to the token, held for the rest of the session once it triggers. Heavy. Teams tend to install this one per project rather than globally, and load it only when the job comes up.

Servers bill, skills cost

A server charges by the month. A skill charges once per session, in context, and then keeps charging it for as long as the session lives.

Before and after

The same question, put to the same model twice: once as it comes, and once with these instructions loaded.

No worked example has been published for this skill yet.

Adoption

Installsnone yet

Ratingno reviews yet

The procedure it runs

The procedure has not been published here. It is in the skill’s own SKILL.md, which its author has not sent to the marketplace yet.

Prose, not code

These steps are written for a model to follow, not executed by a runtime. It can still be told to skip one, and it will say so when it does.

Servers it uses

None. This skill calls no MCP servers at all.

Everything it needs is in the instructions, so it works in a project with nothing connected — the model reads the file and changes how it works with what it can already reach.

It writes no files and reaches no network. All it changes is how the model reasons and writes.

What it asks for

Writes filesno

Network accessno

Read from the allowed-tools line of this skill’s own SKILL.md. A skill grants no permissions of its own — it can only ask for tools your client already has.

What it will not do

Every skill is narrow, and the useful ones say where they stop. These are the jobs this one is the wrong tool for.

What this skill is not for has not been published here. Nothing is implied by that: it is a section the author has not filled in.

If this is not it

12 other skills in Data Science & ML

What is in the bundle

14 files, 38.1 kB on disk. A bundle is text throughout: the instructions the model reads, plus the templates it fills in.

SKILL.md8.3 kB
references/ANYWIDGET.md3.8 kB
references/COLUMNS.md1.1 kB
references/CONFIGURATION.md1.0 kB
references/DEPLOYMENT.md1.3 kB
references/EXPENSIVE.md1.8 kB
references/EXPORTS.md2.3 kB
references/PYTEST.md5.3 kB
references/REACTIVITY.md1.9 kB
references/SQL.md1.6 kB
references/STATE.md2.5 kB
references/TOP-LEVEL-IMPORTS.md1.7 kB
references/UI.md3.8 kB
references/WATCHING.md1.7 kB

What is not in it

No dependencies and nothing executable: a skill is text the agent reads, so the bundle is 14 files you can review in full before installing. The Apache-2.0 licence covers the templates and examples as well as the instructions.

Install

Installing copies the bundle into your project. Nothing runs at install time — the files sit on disk until the model reads them.

$29 once

marimo Notebook · Apache-2.0 · marimo-team

one-time

Price$29 once

LicenceApache-2.0 — the author’s, unchanged by this purchase

Paid throughStripe, once, on the card you add at the checkout

Keeps workingfor good — the files are yours once they are on disk

Updatesevery update its author ships, delivered through this account

You can read the whole bundle before paying — the SKILL.md above is the product, not a preview of it. What the money buys is the delivery: the folder packaged and handed to your machine by key, every update its author ships, and our support if it does not do what this listing says. The terms of use are Apache-2.0, set by the author and unchanged by buying it here.

Payment runs through Stripe, on a page like this one rather than a redirect. Once there is an account it joins the same mcprush invoice as everything else you run, so there is never a second card to enter.

Which clients pick it up on their own

A skill is a folder of text. A client with a skills folder reads it without being told; everywhere else the same text works, it is just handed to the model rather than found.

Claude Code.claude/skills/

Claude Desktop

ChatGPT

Cursor.cursor/skills/

VS Code.github/skills/

Codex CLI.agents/skills/

Gemini CLI.gemini/skills/

Grok.grok/skills/

Zed.agents/skills/

Windsurf.windsurf/skills/

Agent SDK.claude/skills/

HTTP / API

This release

Versionnot versioned

Publishedno release date on file

Price$29

Referencemarimo-team/marimo-notebook

Versions

Its author publishes no version number, so there is nothing here to pin to: what you install is the folder as it stands today. Instructions change more often than APIs do — a skill can be rewritten entirely without anything it depends on moving.

No earlier releases have been published to the marketplace.

Pinning

Nothing to pin to: this skill carries no version number of its own. What you install is what the folder holds on the day you install it.

Reviews

—no reviews yet · no installs yet

Nobody has reviewed this skill yet. The rating is the mean of the reviews written here, so there is none until somebody writes the first.

Who can post

Only accounts that have had the skill installed for fourteen days, so a review is written after living with it rather than after reading it. Publishers may reply once.

Who wrote it

marimo-team

Publishes on mcprush.

0 servers listed1 skill listednot claimed

Profile

Publisher

Servers0