chore(skills): reserve the send-transactional-email skill name

.agents/skills/writing-skills/SKILL.md

@@ -40,7 +40,7 @@ hogli unsync:skill -- --name <skill-name>
 
 Distribution is automatic after merge — CI publishes to [PostHog/skills](https://github.com/PostHog/skills).
 
-This repo is not the only source. [`PostHog/context-mill`](https://github.com/PostHog/context-mill) publishes the omnibus skills — `instrument-integration`, `instrument-product-analytics`, `instrument-feature-flags`, `instrument-error-tracking`, `instrument-llm-analytics`, `instrument-logs`, `instrument-metrics` — and **every shipping consumer overlays them on top of this repo's**, so context-mill wins on a same-named skill. `hogli lint:skills` fails if you add one of those names under `products/*/skills/`; change the context-mill source instead. Local builds are the opposite case: they carry no omnibus skills at all, so anything that depends on one has to overlay it or fail loudly. See [Context-mill skills override this repo's](../../../docs/published/handbook/engineering/ai/writing-skills.md#context-mill-skills-override-this-repos) for the merge sites.
+This repo is not the only source. [`PostHog/context-mill`](https://github.com/PostHog/context-mill) publishes the omnibus skills — `instrument-integration`, `instrument-product-analytics`, `instrument-feature-flags`, `instrument-error-tracking`, `instrument-llm-analytics`, `instrument-logs`, `instrument-metrics`, `send-transactional-email` — and **every shipping consumer overlays them on top of this repo's**, so context-mill wins on a same-named skill. `hogli lint:skills` fails if you add one of those names under `products/*/skills/`; change the context-mill source instead. Local builds are the opposite case: they carry no omnibus skills at all, so anything that depends on one has to overlay it or fail loudly. See [Context-mill skills override this repo's](../../../docs/published/handbook/engineering/ai/writing-skills.md#context-mill-skills-override-this-repos) for the merge sites.
 
 ## When to write a skill
 

docs/published/handbook/engineering/ai/writing-skills.md

@@ -426,8 +426,8 @@ This repo is not the only source of shipped skills.
 [`PostHog/context-mill`](https://github.com/PostHog/context-mill) assembles the "omnibus" skills
 from posthog.com docs and publishes them as `skills-mcp-resources.zip`:
 `instrument-integration`, `instrument-product-analytics`, `instrument-feature-flags`,
-`instrument-error-tracking`, `instrument-llm-analytics`, `instrument-logs`, and `instrument-metrics`.
-These are the skills behind PostHog Desktop's setup buttons and the wizard.
+`instrument-error-tracking`, `instrument-llm-analytics`, `instrument-logs`, `instrument-metrics`, and `send-transactional-email`.
+The `instrument-*` skills are behind PostHog Desktop's setup buttons and the wizard.
 
 Every consumer below unzips `dist/skills.zip` first and then unzips context-mill on top,
 so **context-mill wins on any skill they both define**.

products/feature_flags/skills/README.md

@@ -38,7 +38,7 @@ So:
 - **Do not add a second skill covering the same trigger**, for example `wrapping-code-in-feature-flags`.
   Two entry points for one job means agents pick one at random and the two drift.
   A rename needs an atomic rename and migration agreed with the skills-distribution owner.
-- The same applies to the other six omnibus skills: `instrument-integration`, `instrument-product-analytics`, `instrument-error-tracking`, `instrument-llm-analytics`, `instrument-logs`, and `instrument-metrics`.
+- The same applies to the other seven omnibus skills: `instrument-integration`, `instrument-product-analytics`, `instrument-error-tracking`, `instrument-llm-analytics`, `instrument-logs`, `instrument-metrics`, and `send-transactional-email`.
 
 Baseline trigger coverage lives in [`products/feature_flags/evals/eval_instrument_flags.py`](../evals/eval_instrument_flags.py).
 It grades the context-mill skill itself, so it needs that skill present in the sandbox and refuses to run without it — read its module docstring before running it.

products/posthog_ai/scripts/build_skills/reserved_names.py

@@ -15,6 +15,7 @@
         "instrument-llm-analytics",
         "instrument-logs",
         "instrument-metrics",
+        "send-transactional-email",
     }
 )
 

products/skills/backend/bundled_skills.py

@@ -26,6 +26,8 @@
         "instrument-error-tracking",
         "instrument-llm-analytics",
         "instrument-logs",
+        "instrument-metrics",
+        "send-transactional-email",
     }
 )