CLI reference

This reference is generated from cli-spec.json, the machine-readable specification the rendlio build emits, so it cannot drift from the binary. It is a compatibility promise from first public release: flags are never repurposed, removals go through one minor version of deprecation warnings, and exit-code meanings never change.

Invocation

rendlio <command> [arguments] [options]

• Binary/command name: rendlio. Distributed as a .NET global tool (Rendlio.Tool), self-contained archives per platform, and a container image — see Downloads.
• An unknown command prints usage on stderr and exits 3.
• Stream discipline: all human and diagnostic text goes to stderr. stdout carries only document bytes, and only when -o - is used. Report JSON goes to the --report path (or stays a stderr summary).

Commands

Command	Summary
rendlio convert	Convert a workbook to PDF, PDF/A-2b or PNG.
rendlio diagnose	Analyse a workbook and report what a conversion would do — never writes documents, never exposes cell contents.
rendlio license	Inspect or verify the licence Rendlio would use.
rendlio fonts	Print the resolved font table.
rendlio version	Print the version banner.

Global options

These apply to every command.

Option	Value	Default	Env var	Milestone	Meaning
--license	PATH|community	—	RENDLIO_LICENSE	M1	Licence file to use — the first step of licence resolution. community asserts the Community tier when a community licence file is present.

Environment variables

Precedence: flag > environment variable > default. The effective values are echoed into report.options, so a report always shows what actually applied.

Variable	Meaning
RENDLIO_LICENSE	Licence file path or inline licence text (step 2 of licence resolution).
RENDLIO_FONTS_DIR	Path list of user font directories. The environment form of --fonts-dir.
RENDLIO_CULTURE	Same as --culture.
RENDLIO_RECALCULATE	Same as --recalculate (strict-v1 planned, M4).
RENDLIO_TIMEOUT	Wall-clock timeout, whole seconds. The environment form of --timeout.
RENDLIO_MAX_MEMORY	Memory soft cap, in bytes — note that the --max-memory flag takes MB.
RENDLIO_MAX_*	Every quantitative resource-limit override — the full registry (file size, ZIP entries, XML depth, cell counts, …).
RENDLIO_SANDBOX	=1 enables sandbox hardening for untrusted-upload hosts: user font directories and system fonts are hard-disabled (bundled fonts only), --recalculate=strict-v1 is refused, the default timeout tightens to 60 s, and any option the sandbox forbids fails with W8112, exit 3 — rather than being silently ignored.
NO_COLOR	Disables colored stderr output.

Exit codes

Normative — the meanings never change.

Code	Meaning
0	clean
1	rendered with warnings
2	unsupported content present
3	invalid input
4	resource limit hit
5	internal error

Scripting contract: exit <= 2 means the document exists and is complete per the report. The one exception is a --recalculate=strict-v1 refusal, which produces no document — scripts using strict-v1 must check result.status. Above that nothing is written: on 3 the message says exactly what was invalid and the remedy; on 4 partial outputs are deleted and the message names the limit and its override; 5 is a bug, never silently swallowed — it asks you to file an issue with a --verbose log. CI users typically treat <= 1 as pass and 2 as review; see the exit-code contract for ready-made pipeline shapes.

Licence resolution

The engine resolves at most one licence source — first match wins, no merging:

1. --license <path>
2. RENDLIO_LICENSE (a file path or an inline licence text)
3. ./Rendlio.license (current working directory)
4. ~/.rendlio/Rendlio.license
5. None ⇒ watermark mode + W9001

--license community asserts the Community tier when a community licence file is present; bare community without a minted file is invalid (exit 3) — the free tier still requires the self-serve-minted file. Details: Licensing guide.

The stderr summary

At the end of every convert and diagnose, a one-screen summary derived only from the report:

Rendlio 0.3.1 → invoice.pdf (7 pages, 262 ms)
  ~ 1 approximated: timePeriod conditional format (evaluated at 2026-08-19)
  ✘ 2 unsupported: stacked bar chart — Summary!chart2 (see report)
  ⚠ fonts: 'Aptos Narrow' missing → 'Carlito' substituted (layout may shift)
  exit 2 · full report: report.json · docs: rendlio.com/docs/report

Convert-mode reports carry deviations only, so no “features rendered” line is printed. Plain ASCII fallback when the console lacks Unicode. --quiet suppresses all but errors.

Stability promise

From first public release: flags are never repurposed; removals go through one minor version of deprecation warnings; exit-code meanings never change; the report and IR schemas are versioned independently (see compatibility report).