diff --git a/packages/opencode/src/plugin/openai/codex.ts b/packages/opencode/src/plugin/openai/codex.ts
index 89b4f322d0..6ead52c813 100644
--- a/packages/opencode/src/plugin/openai/codex.ts
+++ b/packages/opencode/src/plugin/openai/codex.ts
@@ -297,8 +297,11 @@ export async function CodexAuthPlugin(input: PluginInput, options: CodexAuthPlug
               if (ALLOWED_MODELS.has(model.api.id)) return true
               if (DISALLOWED_MODELS.has(model.api.id)) return false
               if (model.api.id === "gpt-5.6") return false
-              const match = model.api.id.match(/^gpt-(\d+(?:\.\d+)?)/)
-              return match ? parseFloat(match[1]) > 5.4 : false
+              const match = model.api.id.match(/^gpt-(\d+)(?:\.(\d+))?/)
+              if (!match) return false
+              const major = Number(match[1])
+              const minor = Number(match[2] ?? 0)
+              return major > 5 || (major === 5 && minor > 4)
             })
             .map(([modelID, model]) => [
               modelID,
diff --git a/packages/opencode/test/plugin/codex.test.ts b/packages/opencode/test/plugin/codex.test.ts
index a50f214447..159f7806a7 100644
--- a/packages/opencode/test/plugin/codex.test.ts
+++ b/packages/opencode/test/plugin/codex.test.ts
@@ -331,12 +331,24 @@ describe("plugin.codex", () => {
     ["gpt-6", true],
     ["gpt-6.0-astra", true],
     ["gpt-7", true],
+    ["gpt-10", true],
+    ["gpt-5.5-astra", true],
+    ["gpt-5.9", true],
+    ["gpt-5.10", true],
+    ["gpt-5.10-astra", true],
+    ["gpt-5.40", true],
     ["gpt-5", false],
+    ["gpt-5.4-astra", false],
+    ["gpt-5.04-astra", false],
     ["gpt-4.1", false],
+    ["gpt-4.99", false],
     ["gpt-5.5-pro", false],
     ["gpt-5.6", false],
+    ["gpt-6garbage", true],
+    ["gpt-6.", true],
+    ["gpt-6.1.2", true],
     ["not-a-gpt-model", false],
-  ])("filters OAuth model %s with integer or decimal versions", async (id, allowed) => {
+  ])("filters OAuth model %s by GPT major and minor versions", async (id, allowed) => {
     const hooks = await CodexAuthPlugin({} as never)
     const provider = {
       models: {