diff --git a/skills/azure-devops-cli/SKILL.md b/skills/azure-devops-cli/SKILL.md
index c8e420fb5..b2a5298cd 100644
--- a/skills/azure-devops-cli/SKILL.md
+++ b/skills/azure-devops-cli/SKILL.md
@@ -79,6 +79,61 @@ az artifacts       # Azure Artifacts
 └── universal      # Universal Packages
 ```
 
+## Posting long comments on Windows
+
+On Windows the `az` command resolves to `az.cmd`, a batch wrapper invoked by `cmd.exe`. The whole command line is capped at ~8191 characters, so a long `--discussion`, `--description`, or `--content` value can be silently truncated or fail. Detect the shell before composing a long argument and route accordingly. Skipping this is the most common reason the agent burns 3-5 turns falling back to raw token retrieval and REST calls.
+
+### Detect the shell first
+
+| Environment | Signal | Action |
+|---|---|---|
+| PowerShell on Windows | `$IsWindows -eq $true` and `$PSVersionTable.PSVersion` is set | Use `azps.ps1` (see below) |
+| PowerShell on macOS / Linux | `$IsWindows -eq $false` | Plain `az` is fine, no cmd.exe wrapper |
+| bash / zsh / sh | `$BASH_VERSION` or `$ZSH_VERSION` set, or `uname` works | Plain `az` is fine, no cmd.exe wrapper |
+| Windows `cmd.exe` | `%ComSpec%` ends in `cmd.exe`, no `$PSVersionTable` | Use `azps.ps1` if PowerShell is installed, otherwise see `az devops invoke` fallback below |
+
+### Option 1: `azps.ps1` (PowerShell on Windows)
+
+`azps.ps1` ships with the Azure CLI installer and invokes the Python entry point directly. No `cmd.exe` length cap.
+
+```powershell
+# Read the long body into a variable and pass it through. No quoting headaches.
+$body = Get-Content -Raw .\comment.md
+azps.ps1 boards work-item update --id 1234 --discussion $body
+```
+
+### Option 2: dedicated `--file-path` flag where Azure CLI offers one
+
+Some commands have a native file flag and you should prefer it over any inline body:
+
+- `az devops wiki page create` and `az devops wiki page update` take `--file-path` (with optional `--encoding`).
+- Use it on any shell, including Windows.
+
+```bash
+az devops wiki page create --path 'My page' --wiki myproject --file-path ./page.md --encoding utf-8
+```
+
+### Option 3: `az devops invoke` fallback
+
+When no `--file-path` exists (work-item `--discussion`, PR `--description`) and you're not in PowerShell, post the body via the underlying REST API. `az devops invoke` runs inside the Python entry point, so it isn't subject to the `cmd.exe` cap either, and it takes the request body from a file with `--in-file`:
+
+```bash
+# Post a long discussion comment to work item 1234.
+# REST: POST /{project}/_apis/wit/workItems/{id}/comments?api-version=7.0-preview.3
+az devops invoke \
+  --area wit --resource comments \
+  --route-parameters project={project} workItemId=1234 \
+  --api-version 7.0-preview.3 \
+  --http-method POST \
+  --in-file ./comment.json
+```
+
+Where `comment.json` is `{ "text": "<long markdown body>" }`. This is the universal escape hatch when neither `azps.ps1` nor `--file-path` is available. `az devops invoke` itself accepts `--in-file` natively.
+
+### Don't rely on `@<file>` for plain string args
+
+The Azure CLI `@<file>` convention is documented for JSON parameters (see [the official quoting guide](https://learn.microsoft.com/en-us/cli/azure/use-azure-cli-successfully-quoting)). It is not guaranteed to expand plain string args like `--discussion` or `--description`, so don't reach for it as a substitute for the three options above.
+
 ## Reference Files
 
 Read the relevant reference file based on the user's task. Each file contains complete command syntax and examples for its domain.
diff --git a/skills/azure-devops-cli/references/boards-and-iterations.md b/skills/azure-devops-cli/references/boards-and-iterations.md
index b1c99a71a..7de6486e8 100644
--- a/skills/azure-devops-cli/references/boards-and-iterations.md
+++ b/skills/azure-devops-cli/references/boards-and-iterations.md
@@ -56,6 +56,10 @@ az boards work-item create \
   --type Bug \
   --discussion "Initial investigation completed"
 
+# For a long --discussion body on Windows, see "Posting long comments on Windows"
+# in SKILL.md. Short version: use azps.ps1 in PowerShell, or fall back to
+# 'az devops invoke' with --in-file when no native --file-path flag is available.
+
 # Open in browser after creation
 az boards work-item create --title "Bug" --type Bug --open
 ```
@@ -85,6 +89,14 @@ az boards work-item update \
   --id {work-item-id} \
   --discussion "Work in progress"
 
+# Long comment on Windows: read the body into a PowerShell variable and call
+# azps.ps1 instead of az.cmd, or fall back to 'az devops invoke' with --in-file.
+# Full guidance in SKILL.md under "Posting long comments on Windows".
+#
+# PowerShell example:
+#   $body = Get-Content -Raw .\comment.md
+#   azps.ps1 boards work-item update --id 1234 --discussion $body
+
 # Update with custom fields
 az boards work-item update \
   --id {work-item-id} \