feat(config): add context compression policy

core/config/meta/registry.go

@@ -182,6 +182,64 @@ func DefaultRegistry() map[string]FieldMetaOverride {
 			Advanced: true,
 			Order:    22,
 		},
+		"compression.enabled": {
+			Section:     "llm",
+			Label:       "Context Compression",
+			Description: "Enable compression of chat history before it reaches the model context limit",
+			Component:   "checkbox",
+			Advanced:    true,
+			Order:       24,
+		},
+		"compression.trigger_at_ratio": {
+			Section:     "llm",
+			Label:       "Compression Trigger Ratio",
+			Description: "Fraction of the model context window that starts compression",
+			Component:   "slider",
+			Min:         f64(0),
+			Max:         f64(1),
+			Step:        f64(0.05),
+			Advanced:    true,
+			Order:       25,
+		},
+		"compression.keep_tail_tokens": {
+			Section:     "llm",
+			Label:       "Compression Tail Tokens",
+			Description: "Number of newest conversation tokens to keep outside the summary",
+			Component:   "number",
+			Min:         f64(0),
+			Advanced:    true,
+			Order:       26,
+		},
+		"compression.max_summary_tokens": {
+			Section:     "llm",
+			Label:       "Maximum Summary Tokens",
+			Description: "Maximum number of tokens produced by context compression",
+			Component:   "number",
+			Min:         f64(0),
+			Advanced:    true,
+			Order:       27,
+		},
+		"compression.compressor_model": {
+			Section:              "llm",
+			Label:                "Compressor Model",
+			Description:          "Chat model used to summarize context; empty uses this model",
+			Component:            "model-select",
+			AutocompleteProvider: ProviderModelsChat,
+			Advanced:             true,
+			Order:                28,
+		},
+		"compression.on_post_compression_overflow": {
+			Section:     "llm",
+			Label:       "Post-compression Overflow",
+			Description: "Action to take when compressed context still exceeds the context limit",
+			Component:   "select",
+			Options: []FieldOption{
+				{Value: "drop_oldest_summary", Label: "Drop Oldest Summary"},
+				{Value: "error", Label: "Return Error"},
+			},
+			Advanced: true,
+			Order:    29,
+		},
 		"cache_type_k": {
 			Section:     "llm",
 			Label:       "KV Cache Type (K)",

core/config/model_config.go

@@ -80,6 +80,7 @@ type ModelConfig struct {
 
 	FunctionsConfig functions.FunctionsConfig `yaml:"function,omitempty" json:"function,omitempty"`
 	ReasoningConfig reasoning.Config          `yaml:"reasoning,omitempty" json:"reasoning,omitempty"`
+	Compression     CompressionConfig         `yaml:"compression,omitempty" json:"compression,omitempty"`
 
 	// ReasoningEffort is the default reasoning effort (none|minimal|low|medium|high)
 	// for this model. A per-request reasoning_effort overrides it. It is forwarded
@@ -148,6 +149,18 @@ type ModelConfig struct {
 	Limits       LimitsConfig       `yaml:"limits,omitempty" json:"limits,omitempty"`
 }
 
+// CompressionConfig controls opt-in compression of chat history before inference.
+// The request middleware consumes this configuration; keeping it on ModelConfig
+// lets operators select a policy per context window and model workload.
+type CompressionConfig struct {
+	Enabled                   bool    `yaml:"enabled,omitempty" json:"enabled,omitempty"`
+	TriggerAtRatio            float64 `yaml:"trigger_at_ratio,omitempty" json:"trigger_at_ratio,omitempty"`
+	KeepTailTokens            int     `yaml:"keep_tail_tokens,omitempty" json:"keep_tail_tokens,omitempty"`
+	MaxSummaryTokens          int     `yaml:"max_summary_tokens,omitempty" json:"max_summary_tokens,omitempty"`
+	CompressorModel           string  `yaml:"compressor_model,omitempty" json:"compressor_model,omitempty"`
+	OnPostCompressionOverflow string  `yaml:"on_post_compression_overflow,omitempty" json:"on_post_compression_overflow,omitempty"`
+}
+
 // @Description Admission-control limits applied per request. The
 // admission middleware enforces these before invoking the handler;
 // requests that exceed a limit get 503 with a Retry-After hint so

core/config/model_config_test.go

@@ -52,6 +52,30 @@ parameters:
 		Expect(valid).To(BeTrue())
 	})
 
+	It("round-trips context compression settings", func() {
+		raw := []byte(`
+name: compressed-chat
+backend: llama-cpp
+parameters:
+  model: chat.gguf
+compression:
+  enabled: true
+  trigger_at_ratio: 0.75
+  keep_tail_tokens: 8000
+  max_summary_tokens: 2048
+  compressor_model: fast-summarizer
+  on_post_compression_overflow: error
+`)
+		var cfg ModelConfig
+		Expect(yaml.Unmarshal(raw, &cfg)).To(Succeed())
+		Expect(cfg.Compression.Enabled).To(BeTrue())
+		Expect(cfg.Compression.TriggerAtRatio).To(Equal(0.75))
+		Expect(cfg.Compression.KeepTailTokens).To(Equal(8000))
+		Expect(cfg.Compression.MaxSummaryTokens).To(Equal(2048))
+		Expect(cfg.Compression.CompressorModel).To(Equal("fast-summarizer"))
+		Expect(cfg.Compression.OnPostCompressionOverflow).To(Equal("error"))
+	})
+
 	It("derives a managed snapshot filename without replacing the logical model", func() {
 		const cacheKey = "0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef"
 		cfg := ModelConfig{

docs/content/features/context-compression.md

@@ -0,0 +1,35 @@
+---
+title: "Context compression"
+description: "Configure automatic compression for long chat histories"
+---
+
+Context compression is an opt-in, per-model policy for chat requests that approach
+the model context limit. The configuration is disabled by default and does not
+change existing requests unless `enabled` is true.
+
+```yaml
+name: long-context-chat
+backend: llama-cpp
+parameters:
+  model: chat-model.gguf
+compression:
+  enabled: true
+  trigger_at_ratio: 0.75
+  keep_tail_tokens: 8000
+  max_summary_tokens: 2048
+  compressor_model: fast-summarizer
+  on_post_compression_overflow: drop_oldest_summary
+```
+
+The fields reserve the model-level contract used by the chat request compressor:
+
+- `trigger_at_ratio` selects the fraction of `context_size` that starts compression.
+- `keep_tail_tokens` protects the newest part of the conversation from compression.
+- `max_summary_tokens` limits the generated summary.
+- `compressor_model` selects a secondary model. An empty value selects the primary model.
+- `on_post_compression_overflow` selects `drop_oldest_summary` or `error` when the compressed request still exceeds the context limit.
+
+{{% notice warning %}}
+The configuration schema is available, but the request-compression middleware is
+still under development. Enabling it does not transform requests yet.
+{{% /notice %}}