# kcode-k1-chat-codex-codec 0.7.0
Concrete K1/Codex codec consumed by `kcode-k1-chat-thread-main-actor` under `K1-CHAT-AGENT-OUTPUT-001 r1`.
`Codec` implements `kcode_k1_codex_adapter::BoxCodec`. The native `call_ktool` wrapper accepts exactly `{"name": <string>, "arguments": <JSON>}` and produces a validated dispatchable `BoxValue::Call`. The native `agent_message` action accepts exactly `{"message": <nonempty string>}` and produces a distinct nondispatchable `BoxValue::AgentMessage`. Every other native name or argument shape is rejected without panicking. Inner Ktool arguments retain deterministic JSON serialization, and actions contribute no model text.
`project` renders every canonical `ChatBox` as `[Box <one-based ID> | <box type>]\n<contents>` without a kind whitelist. `open_agent_response` renders the synthetic unpersisted `[Box <ID> | Agent Response]` generation invitation with no body or trailing newline. Hidden fields are omitted from default model projection for token efficiency, not as a security boundary.
The package selects exact `kcode-k1-chat-chatend = "=0.8.1"`. It owns projection and native-action validation only; persistence, submitted-frontier state, provider I/O, dispatch, native tool registration, recovery, HTTP, UI, daemon selection, and deployment remain elsewhere.