diff --git a/docs/model-api-mapping.json b/docs/model-api-mapping.json
index f3776155f..c3668a70c 100644
--- a/docs/model-api-mapping.json
+++ b/docs/model-api-mapping.json
@@ -1,7 +1,7 @@
 {
   "title": "Model-to-API Endpoint Mapping",
   "description": "Maps AI model families to their supported API endpoints. Used to determine which endpoint (chat/completions vs responses vs messages) a model requires.",
-  "lastUpdated": "2026-08-12T05:43:00Z",
+  "lastUpdated": "2026-08-14T05:41:00Z",
   "sources": {
     "openai": "https://platform.openai.com/docs/models",
     "anthropic": "https://docs.anthropic.com/en/docs/about-claude/models"
@@ -37,11 +37,17 @@
           "endpoints": ["chat_completions", "responses"],
           "notes": "Supports both endpoints. Includes gpt-5.6-sol, gpt-5.6-terra, gpt-5.6-luna per OpenAI SDK ChatModel. gpt-5.6-cyber is responses-only (see separate entry above)."
         },
+        {
+          "family": "gpt-5.5-pro",
+          "patterns": ["gpt-5.5-pro", "gpt-5.5-pro-*"],
+          "endpoints": ["responses"],
+          "notes": "Responses API only (ResponsesOnlyModel per OpenAI OpenAPI spec). More specific than gpt-5.5* pattern below. Includes dated variants like gpt-5.5-pro-2026-04-23."
+        },
         {
           "family": "gpt-5.5",
           "patterns": ["gpt-5.5*"],
           "endpoints": ["chat_completions", "responses"],
-          "notes": "Supports both endpoints. Listed on the official GPT-5.5 model page."
+          "notes": "Supports both endpoints. Listed on the official GPT-5.5 model page. gpt-5.5-pro is responses-only (see separate entry above)."
         },
         {
           "family": "gpt-5.4",
diff --git a/src/copilot-model-catalog-sync.test.ts b/src/copilot-model-catalog-sync.test.ts
index 6e4cdd966..61c333686 100644
--- a/src/copilot-model-catalog-sync.test.ts
+++ b/src/copilot-model-catalog-sync.test.ts
@@ -77,6 +77,7 @@ const SUPPORTED_WITHOUT_CURATED_PRICING = new Set([
 const MAPPING_FAMILIES_NOT_EXPOSED_BY_COPILOT_CLI = new Set([
   'gpt-daybreak', // responses-only preview aliases; not in the Copilot CLI model picker
   'gpt-5-6-cyber', // responses-only gpt-5.6 variant; not in the Copilot CLI model picker
+  'gpt-5-5-pro', // responses-only gpt-5.5 variant; not in the Copilot CLI model picker
   'gpt-5-1-codex-max',
   'gpt-5-codex/pro',
   'o4-mini-deep-research',