# `Pixir.Provider.ResponsesExtensions`
[🔗](https://github.com/Ranvier-Technologies/pixir/blob/main/lib/pixir/provider/responses_extensions.ex#L1)

Responses wire and strict-open runtime policy.

Request shaping is derived only from the frozen `ResponsesBackend` snapshot; it
never consults a model, endpoint, Registry, or prior request. The strict-open path
validates every known event against the generated pinned schema before applying the
exact event-family-owned local correlation limits and portable output policy;
same-named additional properties outside those owners remain ignored, and neither
layer retains remote payload values. The first `open_responses` profile has an empty
extension set and fixed reasoning/nonportable-content boundaries, while the default
ChatGPT/Codex wire keeps its ordered policy and reducer.

# `allowed?`

```elixir
@spec allowed?(Pixir.Providers.ResponsesBackend.t(), atom()) :: boolean()
```

Whether the immutable snapshot permits a typed request extension.

# `applied_ids`

```elixir
@spec applied_ids(Pixir.Providers.ResponsesBackend.t()) :: [String.t()]
```

Safe sorted extension ids applied by this backend snapshot.

# `headers`

```elixir
@spec headers(Pixir.Providers.ResponsesBackend.t()) :: [{String.t(), String.t()}]
```

Return the fixed ordered non-auth headers for a backend mode.

# `omitted_ids`

```elixir
@spec omitted_ids(Pixir.Providers.ResponsesBackend.t()) :: [String.t()]
```

Safe sorted extension ids omitted by this backend snapshot.

# `project_input`

```elixir
@spec project_input(Pixir.Providers.ResponsesBackend.t(), [map()]) :: [map()]
```

Project the folded input without changing content bytes or non-message items.

# `validate_request`

```elixir
@spec validate_request(Pixir.Providers.ResponsesBackend.t(), map(), term()) ::
  :ok | {:error, map()}
```

Validate requested capabilities before routing, body construction, Auth, or transport.

# `validate_stream_event`

```elixir
@spec validate_stream_event(map()) ::
  {:ok, :known | :unknown}
  | {:error, atom()}
  | {:unsupported, :reasoning | :nonportable_output_item | :nonportable_content}
```

Validate pinned schema, local limits, and portability for one strict-open event.

---

*Consult [api-reference.md](api-reference.md) for complete listing*