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Linting Guide

RFC 5545 vs Basic iCal Linting for OTA and PMS Reliability

Use linting as a first gate, then validate real import and booking behavior before release.

Technical evaluators, integrators, and engineering teams comparing validation approaches. Updated 2026-03-14

What linting does well

Linting catches format issues early and improves hygiene.

It does not prove downstream booking behavior, imported coverage, or blocked-date accuracy.

When linting alone is not enough

The linter passes but the OTA still rejects the feed.

The feed imports successfully but the timeline is wrong.

No hard errors appear, but event coverage is incomplete.

Why teams outgrow syntax-only checks

Consumers produce different outcomes from the same feed because interpretation and business rules differ.

Behavior evidence resolves ambiguity faster than prolonged spec debate.

Recommended validation sequence

  1. Step 1

    Run lint checks

    Catch obvious format defects first.

  2. Step 2

    Import as a subscription

    Test realistic consumer behavior using the source URL.

  3. Step 3

    Inspect logs and events

    Confirm imported coverage, statuses, and date windows.

  4. Step 4

    Validate timeline result

    Check the final business outcome rather than stopping at parser success.

When to use each approach

ApproachBest forNot enough for
LintingFormat quality gates and CI checksAvailability incidents and business mismatches
Behavior validationReal sync debugging and release validationPure text conformance in isolation
Both togetherProduction-safe workflowNothing critical omitted

Decision checklist

  • Keep linting as a baseline quality gate.
  • Escalate to behavior validation when blocked dates are wrong.
  • Use known feeds for regression testing.
  • Validate outcomes before release.

Run it live

Need more than a syntax pass?

Import the live ICS URL and validate the final booking behavior, not just the file text.

Validate Beyond Linting

FAQ

Should I stop linting?

No. Keep linting as a baseline quality gate.

What does behavior validation add?

It proves the feed produces the correct availability outcome once it is fetched and imported.

When is linting enough on its own?

Only when you care about text validity in isolation rather than downstream booking behavior.