diff --git a/packages/opencode/src/agent/agent.ts b/packages/opencode/src/agent/agent.ts
index 6fee2fdd..ede8fbf7 100644
--- a/packages/opencode/src/agent/agent.ts
+++ b/packages/opencode/src/agent/agent.ts
@@ -14,6 +14,7 @@ export namespace Agent {
       mode: z.union([z.literal("subagent"), z.literal("primary"), z.literal("all")]),
       topP: z.number().optional(),
       temperature: z.number().optional(),
+      options: z.record(z.any()),
       model: z
         .object({
           modelID: z.string(),
@@ -39,15 +40,18 @@ export namespace Agent {
           todoread: false,
           todowrite: false,
         },
+        options: {},
         mode: "subagent",
       },
       build: {
         name: "build",
         tools: {},
+        options: {},
         mode: "primary",
       },
       plan: {
         name: "plan",
+        options: {},
         tools: {
           write: false,
           edit: false,
@@ -66,6 +70,7 @@ export namespace Agent {
         item = result[key] = {
           name: key,
           mode: "all",
+          options: {},
           tools: {},
         }
       if (value.model) item.model = Provider.parseModel(value.model)
@@ -79,6 +84,11 @@ export namespace Agent {
       if (value.temperature != undefined) item.temperature = value.temperature
       if (value.top_p != undefined) item.topP = value.top_p
       if (value.mode) item.mode = value.mode
+      if (value.options)
+        item.options = {
+          ...item.options,
+          ...value.options,
+        }
     }
     return result
   })
diff --git a/packages/opencode/src/config/config.ts b/packages/opencode/src/config/config.ts
index 2ba82904..96a662b2 100644
--- a/packages/opencode/src/config/config.ts
+++ b/packages/opencode/src/config/config.ts
@@ -173,6 +173,7 @@ export namespace Config {
       tools: z.record(z.string(), z.boolean()).optional(),
       disable: z.boolean().optional(),
       description: z.string().optional().describe("Description of when to use the agent"),
+      options: z.record(z.string(), z.any()).optional().describe("Additional model options passed through to provider"),
       mode: z.union([z.literal("subagent"), z.literal("primary"), z.literal("all")]).optional(),
     })
     .openapi({
diff --git a/packages/opencode/src/session/index.ts b/packages/opencode/src/session/index.ts
index 583f3df7..3d6bf98c 100644
--- a/packages/opencode/src/session/index.ts
+++ b/packages/opencode/src/session/index.ts
@@ -852,20 +852,24 @@ export namespace Session {
       tools[key] = item
     }
 
-    const params = {
-      temperature: model.info.temperature
-        ? (agent.temperature ?? ProviderTransform.temperature(input.providerID, input.modelID))
-        : undefined,
-      topP: agent.topP ?? ProviderTransform.topP(input.providerID, input.modelID),
-    }
-    await Plugin.trigger(
+    const params = await Plugin.trigger(
       "chat.params",
       {
         model: model.info,
         provider: await Provider.getProvider(input.providerID),
         message: userMsg,
       },
-      params,
+      {
+        temperature: model.info.temperature
+          ? (agent.temperature ?? ProviderTransform.temperature(input.providerID, input.modelID))
+          : undefined,
+        topP: agent.topP ?? ProviderTransform.topP(input.providerID, input.modelID),
+        options: {
+          ...ProviderTransform.options(input.providerID, input.modelID),
+          ...model.info.options,
+          ...agent.options,
+        },
+      },
     )
     const stream = streamText({
       onError(e) {
@@ -946,10 +950,7 @@ export namespace Session {
         return false
       },
       providerOptions: {
-        [input.providerID]: {
-          ...ProviderTransform.options(input.providerID, input.modelID),
-          ...model.info.options,
-        },
+        [input.providerID]: params.options,
       },
       temperature: params.temperature,
       topP: params.topP,
diff --git a/packages/plugin/src/index.ts b/packages/plugin/src/index.ts
index d0d484a0..7ea82d2a 100644
--- a/packages/plugin/src/index.ts
+++ b/packages/plugin/src/index.ts
@@ -19,7 +19,7 @@ export interface Hooks {
    */
   "chat.params"?: (
     input: { model: Model; provider: Provider; message: UserMessage },
-    output: { temperature: number; topP: number },
+    output: { temperature: number; topP: number; options: Record<string, any> },
   ) => Promise<void>
   "permission.ask"?: (input: Permission, output: { status: "ask" | "deny" | "allow" }) => Promise<void>
   "tool.execute.before"?: (