feat: update GPT model from gpt-4o-mini to gpt-5-nano

Author: mwbrooks

.claude/CLAUDE.md

@@ -65,7 +65,7 @@ Each sub-package has a `register(app)` function called from `listeners/__init__.
 |--------|-----------------|-------------------|-------------|
 | Agent file | `agent/casey.py` | `agent/support_agent.py` | `agent/casey.py` |
 | App type | `AsyncApp` (fully async) | `App` (sync) | `App` (sync) |
-| Agent definition | `ClaudeSDKClient` with `ClaudeAgentOptions` | `Agent[CaseyDeps](model="gpt-4o-mini")` | `Agent(deps_type=CaseyDeps)` |
+| Agent definition | `ClaudeSDKClient` with `ClaudeAgentOptions` | `Agent[CaseyDeps](model="gpt-5-nano")` | `Agent(deps_type=CaseyDeps)` |
 | Model config | Managed by SDK (Claude models) | Set directly on agent constructor | Passed at runtime via `run_sync(model=DEFAULT_MODEL)` |
 | Tool definition | `@tool` decorated functions via MCP server | `@function_tool` decorated functions | Plain async functions |
 | Tool context param | `args` dict (no context param) | `RunContextWrapper[CaseyDeps]` | `RunContext[CaseyDeps]` |

openai-agents-sdk/.claude/CLAUDE.md

@@ -6,7 +6,7 @@ See the root `../.claude/CLAUDE.md` for monorepo-wide architecture, commands, an
 
 ## OpenAI Agents SDK Specifics
 
-**Agent (`agent/support_agent.py`)** is an `Agent[CaseyDeps]` with the model set directly on the agent (`model="gpt-4o-mini"`). Tools are `@function_tool`-decorated async functions, each in its own file under `agent/tools/`. Execution uses `Runner.run_sync(casey_agent, input=..., context=deps)`.
+**Agent (`agent/support_agent.py`)** is an `Agent[CaseyDeps]` with the model set directly on the agent (`model="gpt-5-nano"`). Tools are `@function_tool`-decorated async functions, each in its own file under `agent/tools/`. Execution uses `Runner.run_sync(casey_agent, input=..., context=deps)`.
 
 **Conversation history** is stored as a generic `list` and must be manually combined with new user input before passing to `Runner.run_sync()`: `input_items = history + [{"role": "user", "content": text}]`. After execution, `result.to_input_list()` is stored back.
 

openai-agents-sdk/README.md

@@ -108,7 +108,7 @@ pip install -r requirements.txt
 
 ### OpenAI Setup
 
-This app uses OpenAI's `gpt-4o-mini` model through the OpenAI Agents SDK.
+This app uses OpenAI's `gpt-5-nano` model through the OpenAI Agents SDK.
 
 1. Create an API key from your [OpenAI dashboard](https://platform.openai.com/api-keys).
 1. Rename `.env.sample` to `.env`.

openai-agents-sdk/agent/support_agent.py

@@ -55,5 +55,5 @@
         check_system_status,
         lookup_user_permissions,
     ],
-    model="gpt-4o-mini",
+    model="gpt-5-nano",
 )

pydantic-ai/.claude/CLAUDE.md

@@ -6,7 +6,7 @@ See the root `../.claude/CLAUDE.md` for monorepo-wide architecture, commands, an
 
 ## Pydantic AI Specifics
 
-**Agent (`agent/casey.py`)** is a Pydantic AI `Agent` with `deps_type=CaseyDeps`. The model is **not** set on the agent (to avoid import-time OpenAI client creation); instead `DEFAULT_MODEL` (`openai:gpt-4o-mini`) is passed at each `run_sync()` call site. Tools are passed via the `tools=[]` constructor parameter (not decorators) so each tool lives in its own file under `agent/tools/`.
+**Agent (`agent/casey.py`)** is a Pydantic AI `Agent` with `deps_type=CaseyDeps`. The model is **not** set on the agent (to avoid import-time OpenAI client creation); instead `DEFAULT_MODEL` (`openai:gpt-5-nano`) is passed at each `run_sync()` call site. Tools are passed via the `tools=[]` constructor parameter (not decorators) so each tool lives in its own file under `agent/tools/`.
 
 **Conversation history** stores `list[ModelMessage]` from Pydantic AI and is passed directly as `message_history=` to `run_sync()`.
 

pydantic-ai/README.md

@@ -108,7 +108,7 @@ pip install -r requirements.txt
 
 ### OpenAI Setup
 
-This app uses OpenAI's `gpt-4o-mini` model through Pydantic AI.
+This app uses OpenAI's `gpt-5-nano` model through Pydantic AI.
 
 1. Create an API key from your [OpenAI dashboard](https://platform.openai.com/api-keys).
 1. Rename `.env.sample` to `.env`.

pydantic-ai/agent/casey.py

@@ -45,7 +45,7 @@
 - If unsure about a user's issue, ask clarifying questions before taking action
 """
 
-DEFAULT_MODEL = "openai:gpt-4o-mini"
+DEFAULT_MODEL = "openai:gpt-5-nano"
 
 casey_agent = Agent(
     deps_type=CaseyDeps,