diff --git a/CHANGELOG.md b/CHANGELOG.md
index 043f339..317eaff 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ This file records what changes **in the product** – process and session state
 ### Changed
 - The AI service's Vercel project builds only when something under `services/ai/` changed: fewer images in its
   container registry and fewer builds. A redeploy after changing its variables must not be skipped (runbook §3.6) (#98).
+- The AI service project deploys only from `main`: pull-request branches create no AI deployment at all, so
+  they no longer use up the Vercel plan's deployment limits (runbook §3.7) (#104).
 - A unit correction is stored like the extraction stores units: „Stk.“, „Stück“ or „Meter“ become the ERP units
   `pcs` and `m`; other units stay as typed. The correction field shows „Stk.“, and the audit event keeps what
   was typed (#96).
diff --git a/docs/technical/deployment-vercel.md b/docs/technical/deployment-vercel.md
index 17dce06..c72f169 100644
--- a/docs/technical/deployment-vercel.md
+++ b/docs/technical/deployment-vercel.md
@@ -77,8 +77,8 @@ creation). The script is all-or-nothing; running it twice fails on "role already
    skips the build unless something under `services/ai/` changed since the last successful deployment
    (`VERCEL_GIT_PREVIOUS_SHA`, else the parent commit; if git cannot compare, it builds). A skipped build
    ends as `CANCELED`; skipped builds may still count against the plan's deployment limits. A new branch
-   without a successful AI deployment compares only its last commit, so an AI preview may be missing there
-   (production is not affected). **A redeploy runs the same step:** after changing a variable of
+   without a successful AI deployment compares only its last commit (since #104 only `main` deploys, see
+   step 7). **A redeploy runs the same step:** after changing a variable of
    `requestflow-ai` (§9), redeploy without the Ignored Build Step (untick it in the Redeploy dialog if offered)
    and check that the deployment reaches **Ready** – `CANCELED` means the new value is not active.
    Every build pushes an image to the project's container registry, which has a maximum number of images on
@@ -87,6 +87,15 @@ creation). The script is all-or-nothing; running it twice fails on "role already
    `vercel vcr image ls dockerfile --project requestflow-ai` and
    `vercel vcr image rm dockerfile <image-id> --project requestflow-ai`), keeping the image of the current
    production deployment and one rollback candidate. Deleting an image is permanent.
+7. **Only `main` deploys (#104):** `services/ai/vercel.json` sets `git.deploymentEnabled` to
+   `{ "**": false, "main": true }` – a push to any other branch (every PR) creates **no** `requestflow-ai`
+   deployment at all, not even a skipped one, so PRs no longer use up the plan's deployment limits. When
+   several patterns match, `true` wins; `**` also covers branch names with `/` (minimatch). A merge to `main`
+   that touches `services/ai/` still deploys production (step 6 decides whether it builds). The setting gates
+   only deployments triggered by a Git push – a redeploy from the dashboard (§9) still works. No AI preview is
+   needed: CI builds the image and checks `/healthz` on AI-image changes (#79), and web previews do not call
+   the AI service (§4: Preview variables stay empty). The preview protection of step 2 only matters if Git
+   deployments of other branches are ever switched back on.
 
 ## 4. Vercel project
 
diff --git a/services/ai/vercel.json b/services/ai/vercel.json
index 0f04c79..9047d94 100644
--- a/services/ai/vercel.json
+++ b/services/ai/vercel.json
@@ -1,5 +1,11 @@
 {
   "$schema": "https://openapi.vercel.sh/vercel.json",
   "regions": ["fra1"],
-  "ignoreCommand": "git diff --quiet \"${VERCEL_GIT_PREVIOUS_SHA:-HEAD^}\" HEAD -- ./"
+  "ignoreCommand": "git diff --quiet \"${VERCEL_GIT_PREVIOUS_SHA:-HEAD^}\" HEAD -- ./",
+  "git": {
+    "deploymentEnabled": {
+      "**": false,
+      "main": true
+    }
+  }
 }