Skills

Execution

How Stencila executes documents - kernels, staleness-driven re-execution, execution...

Install

npx skills add stencila/stencila --skill execution -g -a claude-code -y
Repository
stencila/stencila914
Category
Testing
Updated
3d ago
License
Apache-2.0
Context cost
Lightabout 819 tokens
Runs scripts
No, instructions only

What it does

How Stencila executes documents - kernels, staleness-driven re-execution, execution options, and debugging chunks that error or do not re-run. Use when running stencila execute or render, when a code chunk is not re-running, when choosing a language/kernel, or when reading execution errors.

Executing Stencila documents

stencila execute doc.smd runs the executable code in a document and saves the outputs into it. stencila render doc.smd out.html is execute plus encode to output formats. Always invoke non-interactively:

NO_COLOR=1 stencila execute doc.smd --yes
NO_COLOR=1 stencila render doc.smd out.html --yes

Staleness: why a chunk may not re-run

Execution is staleness-driven. A chunk re-runs only when it (or something it depends on) has changed since its last recorded execution. This is why "I edited the prose and re-executed, but the plot didn't regenerate" is expected behaviour, not a bug. Also check the chunk's execution mode in the source: lock prevents re-execution to preserve outputs, always forces re-run every time.

To override staleness:

  • --force-all, re-execute everything regardless of staleness. The first thing to try when outputs look out of date.
  • --skip-code, skip executing code (useful to re-run only other executable node types).
  • --ignore-errors, do not fail the command on execution errors; render what can be rendered.
  • --no-save (execute only), run without writing outputs back to the source document. Use for a reproducibility check that must not mutate files.
  • --dry-run, compile and prepare but do not actually execute.

execute and render share the execution option group, but --no-save is execute-only, and output/encoding options (--to, --theme, etc.) are render-only. Check --help when unsure.

Kernels

Each language executes in a kernel. stencila kernels list shows what is available on this machine. Current kernels include:

Read the whole SKILL.md on GitHub

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