diff --git a/Cargo.toml b/Cargo.toml
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -2,6 +2,7 @@
 name = "indd"
 version = "0.1.0"
 edition = "2024"
+rust-version = "1.95"
 description = "Reader for INDD files and converter to IDML"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/aiongg/indd-utils"
diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -73,6 +73,33 @@ The library also builds for WebAssembly (`wasm32-unknown-unknown`):
 `indd::convert` needs no file system or other host function, and gives
 the same package as a native build (`tools/check_wasm.sh`).
 
+### Natural Language Usage
+
+[`skills/indd-to-idml/SKILL.md`](skills/indd-to-idml/SKILL.md) teaches AI
+coding agents (Claude Code, Codex, Cursor, Gemini) how to check whether
+`indd` and the Rust toolchain (`rust-version` in [`Cargo.toml`](Cargo.toml))
+are already installed on macOS, Linux, or Windows, build `indd` only when
+needed, convert `.indd` and `.indt` files, verify the output zip, and
+report the saved `.idml` path.
+
+Convert a file directly from the skill URL:
+
+```text
+Use the indd-to-idml skill at https://github.com/storytold/indd-utils/tree/main/skills/indd-to-idml to convert "/path/to/brochure.indd" to IDML
+```
+
+Or install the skill for future sessions and convert in one step:
+
+```text
+Use the indd-to-idml skill at https://github.com/storytold/indd-utils/tree/main/skills/indd-to-idml to install the skill, then convert "/path/to/brochure.indd" to IDML
+```
+
+Once installed, ask in plain English:
+
+```text
+Convert "/path/to/brochure.indd" to IDML
+```
+
 
 ## Supported versions
 
diff --git a/skills/indd-to-idml/SKILL.md b/skills/indd-to-idml/SKILL.md
new file mode 100644
--- /dev/null
+++ b/skills/indd-to-idml/SKILL.md
@@ -0,0 +1,203 @@
+---
+name: indd-to-idml
+description: Convert Adobe InDesign (.indd, .indt) files to IDML (.idml) without InDesign using storytold/indd-utils on macOS, Linux, and Windows. Checks whether indd and its dependencies (git, rustup, rustc >= 1.95 per Cargo.toml) are already installed before building or converting. Use when asked to convert .indd or .indt files to .idml, inspect InDesign files, or run indd-utils.
+---
+
+# Converting INDD and INDT Files to IDML (`indd-utils`)
+
+Converts native Adobe InDesign documents (`.indd`) and templates (`.indt`) to
+IDML packages (`.idml`) without InDesign using
+[`storytold/indd-utils`](https://github.com/storytold/indd-utils).
+
+```text
++-----------------------------------------------------------------------+
+| 1. Locate `indd` binary (PATH -> ~/.cargo/bin -> ./target/release)    |
++-----------------------------------+-----------------------------------+
+                                    |
+                     Found? --------+-------- Not Found?
+                       |                          |
+                       v                          v
+                       |        +---------------------------------------+
+                       |        | 2. Check Dependencies (OS-specific)   |
+                       |        |    - Check git & rustc >= 1.95.0      |
+                       |        |    - Ask user before installing tools |
+                       |        |    - Install `indd` to ~/.cargo/bin   |
+                       |        +-----------------+---------------------+
+                       |                          |
+                       +------------+-------------+
+                                    |
+                                    v
++-----------------------------------------------------------------------+
+| 3. Convert & Verify                                                   |
+|    - `indd info <in.indd>`                                            |
+|    - `indd convert <in.indd> <out.idml>`                              |
+|    - Test IDML zip integrity (`designmap.xml`, `Spreads/`, `Stories/`)|
++-----------------------------------------------------------------------+
+```
+
+## Step 1: Check for an Existing `indd` Binary
+
+Check whether `indd` is already built before checking toolchains or compiling
+from source.
+
+### macOS and Linux
+
+Check in order:
+
+1. `which indd`
+2. `$HOME/.cargo/bin/indd`
+3. `./target/release/indd` (if running inside an `indd-utils` checkout)
+
+```bash
+which indd || ls -la "$HOME/.cargo/bin/indd" "./target/release/indd"
+```
+
+### Windows (PowerShell)
+
+Check in order:
+
+1. `Get-Command indd -ErrorAction SilentlyContinue`
+2. `$env:USERPROFILE\.cargo\bin\indd.exe`
+3. `.\target\release\indd.exe` (if running inside an `indd-utils` checkout)
+
+```powershell
+Test-Path "$env:USERPROFILE\.cargo\bin\indd.exe", ".\target\release\indd.exe"
+```
+
+If `indd` exists in any of these locations, skip Step 2 and go to Step 3.
+
+---
+
+## Step 2: Check Dependencies and Install `indd`
+
+Building `indd-utils` from source requires:
+- `git`
+- Rust `>= 1.95.0` (`rust-version = "1.95"` in [`Cargo.toml`](../../Cargo.toml),
+  required for `let_chains` stabilized in 1.88 and `if_let_guard` stabilized in
+  1.95).
+
+**Ask the user before installing:** Never install or update a toolchain
+(`rustup`, MSVC Build Tools) or system package (`apt`, `winget`) without
+confirmation. Show the user the exact commands that will run and wait for
+approval before executing them.
+
+**Compiler PATH shadowing on macOS and Linux:** Homebrew
+(`/opt/homebrew/bin/rustc`) and system package managers (`/usr/bin/rustc`)
+often place an older `rustc` ahead of `~/.cargo/bin/rustc` in `PATH`. Check
+`~/.cargo/bin/rustc --version` directly and pass
+`RUSTC="$HOME/.cargo/bin/rustc"` when running `cargo`.
+
+### macOS
+
+1. Check `git` and `rustc`:
+   ```bash
+   git --version
+   "$HOME/.cargo/bin/rustc" --version
+   ```
+2. If `rustup` is not installed, show the command and ask the user before running:
+   ```bash
+   curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+   ```
+3. If `rustc` is older than `1.95.0`, show the command and ask the user before updating `stable`:
+   ```bash
+   "$HOME/.cargo/bin/rustup" update stable
+   ```
+4. Install `indd` into `~/.cargo/bin/indd`:
+   ```bash
+   env RUSTC="$HOME/.cargo/bin/rustc" "$HOME/.cargo/bin/cargo" install --git https://github.com/storytold/indd-utils.git
+   ```
+   *(If already inside an `indd-utils` checkout, use `--path .` instead of `--git ...`.)*
+
+### Linux
+
+1. Check `git`, C linker (`cc`), and `rustc`:
+   ```bash
+   git --version
+   cc --version
+   "$HOME/.cargo/bin/rustc" --version
+   ```
+   *(On Debian/Ubuntu, if `git` or `cc` is missing, show `sudo apt-get update && sudo apt-get install -y git build-essential curl` and ask the user before running.)*
+2. If `rustup` is not installed, show the command and ask the user before running:
+   ```bash
+   curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+   ```
+3. If `rustc` is older than `1.95.0`, show the command and ask the user before updating `stable`:
+   ```bash
+   "$HOME/.cargo/bin/rustup" update stable
+   ```
+4. Install `indd` into `~/.cargo/bin/indd`:
+   ```bash
+   env RUSTC="$HOME/.cargo/bin/rustc" "$HOME/.cargo/bin/cargo" install --git https://github.com/storytold/indd-utils.git
+   ```
+
+### Windows (PowerShell)
+
+1. Check `git` and `rustc`:
+   ```powershell
+   git --version
+   & "$env:USERPROFILE\.cargo\bin\rustc.exe" --version
+   ```
+2. If `git`, `rustup`, or the MSVC linker is missing, show the required `winget` commands and ask the user before running:
+   ```powershell
+   winget install --id Git.Git -e --source winget
+   winget install --id Rustlang.Rustup -e --source winget
+   winget install Microsoft.VisualStudio.2022.BuildTools --override "--wait --passive --add Microsoft.VisualStudio.Workload.VCTools --includeRecommended"
+   ```
+3. If `rustc` is older than `1.95.0`, show the command and ask the user before updating `stable`:
+   ```powershell
+   & "$env:USERPROFILE\.cargo\bin\rustup.exe" update stable
+   ```
+4. Install `indd.exe` into `%USERPROFILE%\.cargo\bin\indd.exe`:
+   ```powershell
+   $env:RUSTC = "$env:USERPROFILE\.cargo\bin\rustc.exe"
+   & "$env:USERPROFILE\.cargo\bin\cargo.exe" install --git https://github.com/storytold/indd-utils.git
+   ```
+
+---
+
+## Step 3: Convert INDD or INDT to IDML
+
+Using the resolved binary path (`<INDD_BIN>`):
+
+1. Inspect the file header (InDesign version, byte order, database pages, and
+   object count):
+   ```bash
+   <INDD_BIN> info "/path/to/input.indd"
+   ```
+
+2. Convert the file to IDML:
+   ```bash
+   <INDD_BIN> convert "/path/to/input.indd" "/path/to/output.idml"
+   ```
+   - If the user does not give an output path, write to the same directory and
+     basename with an `.idml` extension.
+   - Non-fatal conversion issues print to `stderr` as `warning: ...`.
+
+---
+
+## Step 4: Verify and Report Output
+
+1. Test the output zip archive integrity (`mimetype`, `designmap.xml`,
+   `Spreads/`, `Stories/`, `MasterSpreads/`, `Resources/`):
+   - macOS and Linux:
+     ```bash
+     unzip -t "/path/to/output.idml"
+     ```
+   - Windows (PowerShell — decompresses every entry stream to verify CRC-32 integrity):
+     ```powershell
+     Add-Type -AssemblyName System.IO.Compression.FileSystem
+     $z = [IO.Compression.ZipFile]::OpenRead("C:\path\to\output.idml")
+     try { foreach ($e in $z.Entries) { $s = $e.Open(); $s.CopyTo([IO.Stream]::Null); $s.Close() } } finally { $z.Dispose() }
+     ```
+
+2. If warnings were printed or the user asks what was skipped, run `indd audit`:
+   ```bash
+   <INDD_BIN> audit "/path/to/input.indd"
+   ```
+
+3. Report the converted file location clearly to the user:
+   - Show the full path to the saved `.idml` file (using a clickable
+     `[filename.idml](file:///absolute/path/to/filename.idml)` link when
+     supported) along with its file size.
+   - Include the source InDesign version from `indd info` and note whether the
+     conversion finished cleanly or emitted any warnings.