Add DeepSeek platform + ChatCompletions dialect system (provider 3)

The 6th registry row: id "deepseek", DEEPSEEK_API_KEY > auth.json
"deepseek" scope, base https://api.deepseek.com (chat rides
{base}/chat/completions per official docs) with KIGI_DEEPSEEK_BASE_URL
override, enrichment-backed metadata (1M context, 384k output cap,
high/max effort menu).

Structural fix the cycle exposed: kigi's Kimi-specific body adaptation
ran UNCONDITIONALLY on every ChatCompletions request. New ChatCompat
dialect, declared per platform row and threaded through SamplerConfig,
ClientDefaults, and the session-persisted SamplingConfig (serde-default
Kimi keeps restored pre-field sessions and BYOK endpoints byte-identical;
production persist seams copy it; subagents inherit it):
- Kimi: full legacy pipeline (dispatch ≡ legacy pinned)
- DeepSeek: thinking:{type, reasoning_effort} per api-docs.deepseek.com
  (server maps low/medium→high, xhigh→max itself; none disables; absent
  leaves the server default)
- Passthrough: OpenAI-style reasoning_effort scalar untouched (unblocks
  Groq and the rest of the OpenAI-compatible list)

Review-confirmed release blocker fixed: kigi replays Kimi's
reasoning_content (and its private model_id) on input assistant
messages — Kimi consumes these, but DeepSeek documents input
reasoning_content as prefix-mode-only (historically a 400) and other
providers don't know either field. The DeepSeek and Passthrough arms now
strip both; Kimi's own pipeline is untouched. Pinned on both message
shapes.

crates/codegen/kigi-shell/src/agent/auth_method.rs

@@ -593,7 +593,8 @@ mod tests {
                 MOONSHOT_CN_METHOD_ID,
                 MOONSHOT_AI_METHOD_ID,
                 "openai",
-                "anthropic"
+                "anthropic",
+                "deepseek"
             ]
         );
         assert_eq!(default_id(&built), Some(XAI_API_KEY_METHOD_ID));
@@ -621,7 +622,8 @@ mod tests {
                 MOONSHOT_CN_METHOD_ID,
                 MOONSHOT_AI_METHOD_ID,
                 "openai",
-                "anthropic"
+                "anthropic",
+                "deepseek"
             ]
         );
         assert_eq!(default_id(&built), Some(CACHED_TOKEN_AUTH_METHOD_ID));
@@ -642,7 +644,8 @@ mod tests {
                 MOONSHOT_CN_METHOD_ID,
                 MOONSHOT_AI_METHOD_ID,
                 "openai",
-                "anthropic"
+                "anthropic",
+                "deepseek"
             ]
         );
         assert_eq!(default_id(&built), Some(CACHED_TOKEN_AUTH_METHOD_ID));
@@ -666,7 +669,8 @@ mod tests {
                 MOONSHOT_CN_METHOD_ID,
                 MOONSHOT_AI_METHOD_ID,
                 "openai",
-                "anthropic"
+                "anthropic",
+                "deepseek"
             ]
         );
         assert_eq!(default_id(&built), None);

crates/codegen/kigi-shell/src/agent/config.rs

@@ -4062,6 +4062,20 @@ pub fn sampling_config_for_model(
         &credentials.base_url,
     );
     let api_backend = info.api_backend.clone();
+    // Managed platform entries speak their registry dialect; BYOK/custom
+    // entries keep the historical Kimi body adaptation.
+    let chat_compat = info
+        .id
+        .as_deref()
+        .and_then(kigi_models::parse_managed_model_key)
+        .map(|(platform, _)| match platform.chat_compat() {
+            kigi_models::PlatformChatCompat::Kimi => kigi_sampling_types::ChatCompat::Kimi,
+            kigi_models::PlatformChatCompat::DeepSeek => kigi_sampling_types::ChatCompat::DeepSeek,
+            kigi_models::PlatformChatCompat::Passthrough => {
+                kigi_sampling_types::ChatCompat::Passthrough
+            }
+        })
+        .unwrap_or_default();
     SamplerConfig {
         api_key: credentials.api_key,
         model: model_name,
@@ -4071,6 +4085,7 @@ pub fn sampling_config_for_model(
         top_p,
         api_backend,
         auth_scheme: credentials.auth_scheme,
+        chat_compat,
         extra_headers,
         context_window: info.context_window.get(),
         reasoning_effort: info.reasoning_effort,

crates/codegen/kigi-shell/src/agent/models_fetch.rs

@@ -1022,6 +1022,107 @@ mod tests {
         );
     }
 
+    /// DeepSeek-cycle e2e: bare OpenAI-shape listing + enrichment efforts
+    /// (high/max) produce ChatCompletions entries whose sampler config
+    /// speaks the DeepSeek thinking dialect.
+    #[tokio::test(flavor = "multi_thread")]
+    #[serial_test::serial]
+    async fn deepseek_listing_enriches_and_maps_dialect() {
+        let platform_server = wiremock::MockServer::start().await;
+        wiremock::Mock::given(wiremock::matchers::method("GET"))
+            .and(wiremock::matchers::path("/models"))
+            .and(wiremock::matchers::header("Authorization", "Bearer sk-ds"))
+            .respond_with(wiremock::ResponseTemplate::new(200).set_body_json(
+                serde_json::json!({ "data": [
+                    { "id": "deepseek-v4-pro", "object": "model", "owned_by": "deepseek" }
+                ]}),
+            ))
+            .expect(1)
+            .mount(&platform_server)
+            .await;
+        let modelsdev_server = wiremock::MockServer::start().await;
+        wiremock::Mock::given(wiremock::matchers::method("GET"))
+            .and(wiremock::matchers::path("/api.json"))
+            .respond_with(wiremock::ResponseTemplate::new(200).set_body_json(
+                serde_json::json!({ "deepseek": { "models": { "deepseek-v4-pro": {
+                    "reasoning": true,
+                    "reasoning_options": [
+                        {"type": "toggle"},
+                        {"type": "effort", "values": ["high", "max"]}
+                    ],
+                    "limit": {"context": 1000000, "output": 384000},
+                    "tool_call": true
+                }}}}),
+            ))
+            .expect(1)
+            .mount(&modelsdev_server)
+            .await;
+        let cache_dir = tempfile::tempdir().unwrap();
+        let _base = kigi_test_support::EnvGuard::set(
+            kigi_models::DEEPSEEK_BASE_URL_ENV,
+            platform_server.uri(),
+        );
+        let _mdev = kigi_test_support::EnvGuard::set(
+            crate::agent::enrichment_fetch::MODELS_DEV_URL_ENV,
+            format!("{}/api.json", modelsdev_server.uri()),
+        );
+        let _mdev_cache = kigi_test_support::EnvGuard::set(
+            crate::agent::enrichment_fetch::MODELS_DEV_CACHE_DIR_ENV,
+            cache_dir.path(),
+        );
+        let endpoints = crate::agent::config::EndpointsConfig::default();
+        let keys = crate::agent::models::PlatformApiKeys::test_single(
+            kigi_models::PlatformId::DeepSeek,
+            "sk-ds",
+        );
+        let result = tokio::task::spawn_blocking(move || {
+            fetch_platform_models_blocking(&endpoints, None, &keys)
+        })
+        .await
+        .unwrap()
+        .expect("fetch must succeed");
+        assert_eq!(result.models.len(), 1);
+        let entry = &result.models[0];
+        assert_eq!(entry.id.as_deref(), Some("deepseek/deepseek-v4-pro"));
+        assert_eq!(entry.context_window.get(), 1_000_000);
+        assert_eq!(entry.max_completion_tokens, Some(384_000));
+        assert_eq!(
+            entry.api_backend,
+            crate::sampling::ApiBackend::ChatCompletions
+        );
+        assert_eq!(
+            entry
+                .reasoning_efforts
+                .iter()
+                .map(|o| o.id.as_str())
+                .collect::<Vec<_>>(),
+            vec!["high", "max"]
+        );
+
+        // The managed id maps to the DeepSeek chat dialect; a BYOK entry
+        // (no managed key) keeps the historical Kimi adaptation.
+        let model_entry = crate::agent::config::ModelEntry::from_config_entry(entry);
+        let creds = crate::agent::config::ResolvedCredentials {
+            api_key: Some("sk-ds".into()),
+            base_url: entry.base_url.clone(),
+            auth_type: kigi_chat_state::AuthType::ApiKey,
+            auth_scheme: Default::default(),
+        };
+        let cfg = crate::agent::config::sampling_config_for_model(&model_entry, creds, None);
+        assert_eq!(cfg.chat_compat, kigi_sampling_types::ChatCompat::DeepSeek);
+        let mut byok = entry.clone();
+        byok.id = Some("my-custom".into());
+        let byok_entry = crate::agent::config::ModelEntry::from_config_entry(&byok);
+        let creds = crate::agent::config::ResolvedCredentials {
+            api_key: Some("sk-x".into()),
+            base_url: byok.base_url.clone(),
+            auth_type: kigi_chat_state::AuthType::ApiKey,
+            auth_scheme: Default::default(),
+        };
+        let cfg = crate::agent::config::sampling_config_for_model(&byok_entry, creds, None);
+        assert_eq!(cfg.chat_compat, kigi_sampling_types::ChatCompat::Kimi);
+    }
+
     #[test]
     fn get_env_keys_parses_strings_and_rejects_non_strings() {
         use crate::agent::config::EnvKeys;

crates/codegen/kigi-shell/src/agent/subagent/mod.rs

@@ -889,6 +889,7 @@ async fn read_parent_sampling_config(
                 top_p: cfg.top_p,
                 api_backend: cfg.api_backend,
                 auth_scheme,
+                chat_compat: cfg.chat_compat,
                 extra_headers,
                 context_window: cfg.context_window.get(),
                 reasoning_effort: cfg.reasoning_effort,

crates/codegen/kigi-shell/src/agent/subagent/tests/mod.rs

@@ -3272,6 +3272,7 @@ fn test_sampling_config(model_slug: &str) -> kigi_sampling_types::SamplingConfig
         temperature: None,
         top_p: None,
         api_backend: Default::default(),
+        chat_compat: Default::default(),
         extra_headers: Default::default(),
         context_window: NonZeroU64::new(256_000).expect("non-zero context window"),
         reasoning_effort: None,

crates/codegen/kigi-shell/src/session/acp_session_impl/model_switch.rs

@@ -53,6 +53,7 @@ impl SessionActor {
                 temperature: sampling_config.temperature,
                 top_p: sampling_config.top_p,
                 api_backend: sampling_config.api_backend.clone(),
+                chat_compat: sampling_config.chat_compat,
                 extra_headers: sampling_config.extra_headers.clone(),
                 context_window: new_context_window,
                 reasoning_effort: sampling_config.reasoning_effort,

crates/codegen/kigi-shell/src/session/acp_session_impl/sampler_turn.rs

@@ -260,6 +260,7 @@ impl SessionActor {
                 temperature: None,
                 top_p: None,
                 api_backend: Default::default(),
+                chat_compat: Default::default(),
                 extra_headers: Default::default(),
                 context_window: std::num::NonZeroU64::new(256_000).unwrap(),
                 reasoning_effort: None,
@@ -312,6 +313,7 @@ impl SessionActor {
             top_p: cfg.top_p,
             api_backend: cfg.api_backend,
             auth_scheme,
+            chat_compat: cfg.chat_compat,
             extra_headers,
             context_window: cfg.context_window.get(),
             reasoning_effort: cfg.reasoning_effort,

crates/codegen/kigi-shell/src/session/acp_session_impl/spawn.rs

@@ -346,6 +346,7 @@ pub(crate) async fn spawn_session_actor(
         temperature: sampling_config.temperature,
         top_p: sampling_config.top_p,
         api_backend: sampling_config.api_backend.clone(),
+        chat_compat: sampling_config.chat_compat,
         extra_headers: sampling_config.extra_headers.clone(),
         context_window: context_window_override.unwrap_or(baseline_context_window),
         reasoning_effort: sampling_config.reasoning_effort,

crates/codegen/kigi-shell/src/session/acp_session_tests/auth_error_no_retry_tests.rs

@@ -847,6 +847,7 @@ async fn set_session_model_invalidates_byok_memo_for_same_model_id() {
                 temperature: None,
                 top_p: None,
                 api_backend: crate::sampling::ApiBackend::ChatCompletions,
+                chat_compat: Default::default(),
                 auth_scheme: Default::default(),
                 extra_headers: Default::default(),
                 context_window: 256_000,

crates/codegen/kigi-shell/src/session/acp_session_tests/cancel_running_task_tests.rs

@@ -44,6 +44,7 @@ async fn persist_ack_waits_for_disk_flush_before_success() {
                 temperature: None,
                 top_p: None,
                 api_backend: Default::default(),
+                chat_compat: Default::default(),
                 auth_scheme: Default::default(),
                 extra_headers: Default::default(),
                 context_window: 100_000,
@@ -87,6 +88,7 @@ async fn persist_ack_waits_for_disk_flush_before_success() {
                     temperature: None,
                     top_p: None,
                     api_backend: Default::default(),
+                    chat_compat: Default::default(),
                     extra_headers: Default::default(),
                     context_window: std::num::NonZeroU64::new(100_000).unwrap(),
                     reasoning_effort: None,
@@ -338,6 +340,7 @@ async fn first_turn_memory_injection_persists_to_chat_history() {
                 temperature: None,
                 top_p: None,
                 api_backend: Default::default(),
+                chat_compat: Default::default(),
                 auth_scheme: Default::default(),
                 context_window: 100_000,
                 force_http1: false,
@@ -381,6 +384,7 @@ async fn first_turn_memory_injection_persists_to_chat_history() {
                     temperature: None,
                     top_p: None,
                     api_backend: Default::default(),
+                    chat_compat: Default::default(),
                     extra_headers: Default::default(),
                     context_window: std::num::NonZeroU64::new(100_000).unwrap(),
                     reasoning_effort: None,
@@ -466,6 +470,7 @@ async fn first_turn_memory_injection_disabled_does_not_persist_to_chat_history()
                 temperature: None,
                 top_p: None,
                 api_backend: Default::default(),
+                chat_compat: Default::default(),
                 auth_scheme: Default::default(),
                 context_window: 100_000,
                 force_http1: false,
@@ -513,6 +518,7 @@ async fn first_turn_memory_injection_disabled_does_not_persist_to_chat_history()
                     temperature: None,
                     top_p: None,
                     api_backend: Default::default(),
+                    chat_compat: Default::default(),
                     extra_headers: Default::default(),
                     context_window: std::num::NonZeroU64::new(100_000).unwrap(),
                     reasoning_effort: None,
@@ -1732,6 +1738,7 @@ async fn cancel_propagates_to_sampler_handle_so_no_further_emission() {
                 temperature: None,
                 top_p: None,
                 api_backend: kigi_sampler::ApiBackend::Responses,
+                chat_compat: Default::default(),
                 auth_scheme: Default::default(),
                 extra_headers: Default::default(),
                 context_window: 100_000,

crates/codegen/kigi-shell/src/session/acp_session_tests/idle_resume_tests.rs

@@ -104,6 +104,7 @@ async fn test_e2e_idle_resume_refreshes_model_metadata() {
                     temperature: None,
                     top_p: None,
                     api_backend: Default::default(),
+                    chat_compat: Default::default(),
                     extra_headers: Default::default(),
                     context_window: std::num::NonZeroU64::new(200_000).unwrap(),
                     reasoning_effort: None,

crates/codegen/kigi-shell/src/session/acp_session_tests/inline_auto_compact_flow_tests.rs

@@ -52,6 +52,7 @@ async fn create_test_actor(
             temperature: None,
             top_p: None,
             api_backend: Default::default(),
+            chat_compat: Default::default(),
             extra_headers: Default::default(),
             context_window: std::num::NonZeroU64::new(context_window)
                 .expect("test context_window must be non-zero"),
@@ -486,6 +487,7 @@ async fn create_test_actor_with_memory(
             temperature: None,
             top_p: None,
             api_backend: Default::default(),
+            chat_compat: Default::default(),
             extra_headers: Default::default(),
             context_window: std::num::NonZeroU64::new(context_window)
                 .expect("test context_window must be non-zero"),
@@ -1240,6 +1242,7 @@ async fn test_e2e_idle_resume_refreshes_model_metadata() {
                     temperature: None,
                     top_p: None,
                     api_backend: Default::default(),
+                    chat_compat: Default::default(),
                     extra_headers: Default::default(),
                     context_window: std::num::NonZeroU64::new(200_000).unwrap(),
                     reasoning_effort: None,

crates/codegen/kigi-shell/src/session/acp_session_tests/memory_config_tests.rs

@@ -104,6 +104,7 @@ async fn create_test_actor_with_memory(
             temperature: None,
             top_p: None,
             api_backend: Default::default(),
+            chat_compat: Default::default(),
             extra_headers: Default::default(),
             context_window: std::num::NonZeroU64::new(context_window)
                 .expect("test context_window must be non-zero"),

crates/codegen/kigi-shell/src/session/acp_session_tests/support.rs

@@ -168,6 +168,7 @@ pub(crate) async fn create_test_actor_ex(
             temperature: None,
             top_p: None,
             api_backend: Default::default(),
+            chat_compat: Default::default(),
             extra_headers: Default::default(),
             context_window: std::num::NonZeroU64::new(context_window)
                 .expect("test context_window must be non-zero"),

crates/codegen/kigi-shell/src/session/compaction.rs

@@ -2149,6 +2149,7 @@ mod inline_auto_compact_flow_tests {
                 temperature: None,
                 top_p: None,
                 api_backend: Default::default(),
+                chat_compat: Default::default(),
                 extra_headers: Default::default(),
                 context_window: std::num::NonZeroU64::new(context_window)
                     .expect("test context_window must be non-zero"),

crates/codegen/kigi-shell/src/session/helpers/session_compact.rs

@@ -1588,6 +1588,7 @@ mod reasoning_compaction_regression_tests {
             temperature: Some(0.7),
             top_p: None,
             api_backend: ApiBackend::ChatCompletions,
+            chat_compat: Default::default(),
             auth_scheme: Default::default(),
             extra_headers: Default::default(),
             context_window: 256_000,

crates/codegen/kigi-shell/src/test_support/lsp_runtime.rs

@@ -44,6 +44,7 @@ pub(crate) fn ctx_with_toggle(toggle: HashMap<String, bool>) -> SubagentSpawnCon
             temperature: None,
             top_p: None,
             api_backend: Default::default(),
+            chat_compat: Default::default(),
             auth_scheme: Default::default(),
             extra_headers: Default::default(),
             context_window: 256_000,