Kindle

Kindle delivery

Deliver an already-downloaded file to the user's Kindle through the zlib CLI, and handle the one-time configuration it depends on. To find or download the book first, use the zlib skill; this skill takes it from a local file to the Kindle.

Preflight

Confirm that zlib is on PATH with the current shell (command -v zlib on POSIX or Get-Command zlib in PowerShell). Sending itself doesn't need a Z-Library session, only Kindle config. If the binary is missing, tell the user to install it with go install github.com/heartleo/zlib/cmd/zlib@latest.

Send — zlib kindle send <file>

Always pass the file path — bare zlib kindle send opens an interactive file picker you can't answer. With a path and no terminal it sends directly and exits, printing success or a clear SMTP error:

zlib kindle send ./books/dune.epub

zlib download <id> --send-to-kindle delivers in one step once Kindle is configured.

First check the config

Before sending, read ~/.config/zlib/kindle.json and check ZLIB_SMTP_PWD. If the file is missing, holds placeholder-looking values (e.g. mykindle@kindle.com, sender@gmail.com), or the password is unset, run the setup walkthrough below before sending. If it looks configured, just send and relay the result.

Configuring Kindle delivery — walk the user through it in conversation

Guide the user step by step — ask one question at a time and wait for each answer, then write the non-secret config with the available filesystem or shell tool. The user only edits the secret env file in step 4.

1. Ask for the Kindle receive address. "What's your Kindle address (xxx@kindle.com)? Find it under Amazon → Manage Your Content and Devices → Preferences → Personal Document Settings." It must be the Amazon-assigned address, not their normal email.

2. Ask for the sender email. Remind them it must be on Amazon's approved-sender list (same Personal Document Settings page) — otherwise Amazon silently drops the file even though SMTP reports success.

3. Derive SMTP from the sender domain — gmail.com → smtp.gmail.com:587, outlook/hotmail → smtp-mail.outlook.com:587, qq.com → smtp.qq.com:587, 163.com → smtp.163.com:465; anything else, ask. Then write the config yourself (create the directory if needed):

   // ~/.config/zlib/kindle.json
   {"to":"<kindle-address>","from":"<sender-email>","smtp_host":"<host>","smtp_port":<port>}

4. Set the SMTP app password — the user edits the env file directly. Never ask for, paste, or echo the password in the chat, and never put it on a command line. zlib reads ZLIB_SMTP_PWD from ~/.config/zlib/.env at startup. Prepare the file and hand the user the exact path plus a one-click open command, then wait for them to confirm they saved it.

   Create the file (if missing) with a template line and print its absolute path. Use the commands for the current shell.

   POSIX shell:

   mkdir -p ~/.config/zlib
   [ -f ~/.config/zlib/.env ] || printf '# zlib secrets — one KEY=value per line\nZLIB_SMTP_PWD=\n' > ~/.config/zlib/.env
   chmod 600 ~/.config/zlib/.env
   echo "Open and edit: $(cd ~/.config/zlib && pwd)/.env"

   PowerShell:

   $configDir = Join-Path $env:USERPROFILE '.config\zlib'
   New-Item -ItemType Directory -Force $configDir | Out-Null
   $envFile = Join-Path $configDir '.env'
   if (-not (Test-Path $envFile)) {
     Set-Content -Encoding utf8 $envFile "# zlib secrets — one KEY=value per line`nZLIB_SMTP_PWD="
   }
   $envFile

   Tell the user to set ZLIB_SMTP_PWD=<app-password> on its own line and save. It must be an app password, not the account password — for Gmail: enable 2FA, generate at https://myaccount.google.com/apppasswords (16 chars; strip spaces). Give them a ready open command for their OS:

   • Windows: notepad "$env:USERPROFILE\.config\zlib\.env"
   • macOS: open -t ~/.config/zlib/.env
   • Linux: ${EDITOR:-nano} ~/.config/zlib/.env