Testing & Debugging

A tight iteration loop catches problems before your users do.

Fix errors as you type

The editor checks your code continuously. Errors are underlined in place, with a message on hover — an unknown function, a wrong argument count, a member access on a value that isn't an object, a type mismatch. Don't publish with errors showing. The graph also won't render flows that don't compile, which is a quick visual signal something's off.

Log with debug.log

Drop a log step anywhere to record a value while you're developing:

log(level: "info", message: `cart total is ${flow.total}`)

Use it to confirm a value is what you expect before a tricky branch. Keep messages short and remove noisy logs before publishing.

Validate before publishing

Before you click Publish, scan for the common mistakes:

• Every inline button's callback_data has a matching flow ... on callback "...".
• Every blocking ask.* handles "timeout".
• Every http.* call has an on error (or uses http.retry).
• Secrets are referenced as global.*, not hardcoded.
• List views handle the empty case.

See the full Production checklist.

A good iteration loop

1. Make one change in the editor.
2. Read the inline errors — fix anything underlined.
3. Glance at the graph — does the flow's shape match your intent?
4. Publish and try it in Telegram with a real /start.
5. Repeat. Small steps make it obvious which change broke something.

Reproducing edge cases

When testing interactive flows:

• Trigger the timeout path by simply not replying to an ask.*.
• Test the empty state by clearing the relevant shared.*/user.* variable in the Variables panel.
• Test error paths by temporarily pointing an HTTP call at a bad URL, or leaving an API key blank.

Common things to recheck

Symptom	Likely cause
Button does nothing	Missing on callback flow for its callback_data
Flow hangs forever	ask.* with no timeout / no "timeout" arm
Text shows ${name} literally	You used ${} outside a backtick template, or {{}}
"Variable not found" at runtime	Reading a scope you never declared, or wrong scope prefix
Webhook rejected (401)	Verification secret missing/blank in the Variables panel

More in Common errors and Gotchas.

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• Common errors
• Gotchas