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ReferenceErrors

ErrorsTools · rule

cli.dev_port_invalid

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A jadpo dev --port flag holds something other than a whole number from 0 to 65535.

Area 14, Tools; not declinable; the next step is usually the agent's.

Why Jadpo refuses it

jadpo dev serves the app at http://localhost:3000, and --port moves it to another port. A port is a whole number from 0 to 65535, and 0 asks the system for any free one. Anything else names no port the app could listen on, so nothing starts rather than the app serving somewhere you didn't ask for.

What it looks like

The port is one past the largest:

shell
jadpo dev --port 65536
jadpo dev

error 65536 isn't a port

reason
A port is a whole number from 0 to 65535; 0 lets the system choose a free one.
next
Use a port such as --port 3000 (agent)
rule
cli.dev_port_invalid
help
https://jadpo.dev/docs/errors/cli.dev_port_invalid

(agent) at the end of the next: line means your coding agent can make the fix itself.

A port written with its host, as an address is, is refused with the port alone to give instead:

shell
jadpo dev --port localhost:8080
jadpo dev

error localhost:8080 isn't a port

reason
A port is a whole number from 0 to 65535; 0 lets the system choose a free one.
next
Give the port alone: --port 8080 (agent)
rule
cli.dev_port_invalid
help
https://jadpo.dev/docs/errors/cli.dev_port_invalid

How to fix it

If you want a port of your own, give its number alone, as the next: line does:

shell
jadpo dev --port 8080

The app serves at http://localhost:8080.

If any free port will do, give 0:

shell
jadpo dev --port 0

The system picks a port, and the screen jadpo dev prints names it.

Markdown for agents: /docs/errors/cli.dev_port_invalid.md.Built from Jadpo main at aee2e8f.