feat(runtime): compact with prefix reuse, rolling, and window-derived budgets

crates/merry-cli/src/cmd.rs

@@ -10,9 +10,8 @@ use merry::profiles::{CodingRuntime, CodingRuntimeBuilder, CodingRuntimeInput};
 use merry_core::{ErrorInfo, PendingToolCall, SessionId, ToolInputSchema};
 use merry_llm::{ModelName, ModelProvider, ModelRetryPolicy};
 use merry_runtime::{
-    AgentLoopConfig, AgentLoopStatus, AutomaticCompactionConfig, RegisteredTool, Runtime,
-    StepContext, StepInput, ToolExecutionContext, ToolExecutionOutcome, ToolExecutor,
-    ToolExecutorFuture,
+    AgentLoopConfig, AgentLoopStatus, CompactionConfig, RegisteredTool, Runtime, StepContext,
+    StepInput, ToolExecutionContext, ToolExecutionOutcome, ToolExecutor, ToolExecutorFuture,
 };
 use schemars::{JsonSchema, Schema, SchemaGenerator};
 use serde::{Deserialize, Serialize};
@@ -189,7 +188,7 @@ pub(crate) struct RuntimeInput<'a> {
     pub(crate) environment: CommandGenerationEnvironment,
     pub(crate) provider: Arc<dyn ModelProvider>,
     pub(crate) model: ModelName,
-    pub(crate) automatic_compaction: AutomaticCompactionConfig,
+    pub(crate) automatic_compaction: CompactionConfig,
     pub(crate) retry_policy: Option<ModelRetryPolicy>,
     pub(crate) context_compaction: Option<RuntimeRoleProviderConfig>,
     pub(crate) skill_roots: Vec<PathBuf>,

crates/merry-cli/src/cmd/tests.rs

@@ -122,7 +122,7 @@ async fn command_generation_runtime_is_read_only_workspace_only() {
         environment: CommandGenerationEnvironment::detect(&workspace),
         provider: Arc::new(provider.clone()),
         model: ModelName::new("debug-model").expect("valid model name"),
-        automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+        automatic_compaction: merry_runtime::CompactionConfig::disabled(),
         retry_policy: None,
         context_compaction: None,
         skill_roots: Vec::new(),
@@ -181,7 +181,7 @@ async fn generate_command_plan_reads_structured_final_output() {
         environment: CommandGenerationEnvironment::detect(&workspace),
         provider: Arc::new(provider),
         model: ModelName::new("debug-model").expect("valid model name"),
-        automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+        automatic_compaction: merry_runtime::CompactionConfig::disabled(),
         retry_policy: None,
         context_compaction: None,
         skill_roots: Vec::new(),
@@ -243,7 +243,7 @@ async fn cmd_check_command_tool_reports_path_availability() {
         environment,
         provider: Arc::new(provider),
         model: ModelName::new("debug-model").expect("valid model name"),
-        automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+        automatic_compaction: merry_runtime::CompactionConfig::disabled(),
         retry_policy: None,
         context_compaction: None,
         skill_roots: Vec::new(),

crates/merry-cli/src/coding/runtime.rs

@@ -10,7 +10,7 @@ use merry_llm::{ModelName, ModelProvider, ModelRetryPolicy};
 use merry_runtime::FileSessionStore;
 #[cfg(test)]
 use merry_runtime::Runtime;
-use merry_runtime::{AutomaticCompactionConfig, LoadedSession, RegisteredTool};
+use merry_runtime::{CompactionConfig, LoadedSession, RegisteredTool};
 use std::{
     path::{Path, PathBuf},
     sync::Arc,
@@ -19,7 +19,7 @@ use std::{
 #[cfg(test)]
 pub(crate) struct CodingRuntimeOptions {
     pub(crate) approval_review: Option<RuntimeRoleProviderConfig>,
-    pub(crate) automatic_compaction: AutomaticCompactionConfig,
+    pub(crate) automatic_compaction: CompactionConfig,
     pub(crate) retry_policy: Option<ModelRetryPolicy>,
     pub(crate) context_compaction: Option<RuntimeRoleProviderConfig>,
     pub(crate) process_backend: ActionProcessBackend,
@@ -36,7 +36,7 @@ pub(crate) struct HeadlessCodingRuntimeInput<'a> {
     pub(crate) model: ModelName,
     pub(crate) process_backend: ActionProcessBackend,
     pub(crate) extra_tools: Vec<RegisteredTool>,
-    pub(crate) automatic_compaction: AutomaticCompactionConfig,
+    pub(crate) automatic_compaction: CompactionConfig,
     pub(crate) retry_policy: Option<ModelRetryPolicy>,
     pub(crate) context_compaction: Option<RuntimeRoleProviderConfig>,
     pub(crate) approval_review: Option<RuntimeRoleProviderConfig>,

crates/merry-cli/src/coding/tests.rs

@@ -31,7 +31,7 @@ fn headless_input<'a>(
             permissioned_process_runner_factory,
         )),
         extra_tools: Vec::new(),
-        automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+        automatic_compaction: merry_runtime::CompactionConfig::disabled(),
         retry_policy: None,
         context_compaction: None,
         approval_review: None,

crates/merry-cli/src/coding/tests/composition.rs

@@ -76,7 +76,7 @@ async fn headless_runtime_uses_coding_agent_profile() {
             permissioned_factory,
         )),
         extra_tools: Vec::new(),
-        automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+        automatic_compaction: merry_runtime::CompactionConfig::disabled(),
         retry_policy: None,
         context_compaction: None,
         approval_review: None,
@@ -149,7 +149,7 @@ async fn headless_runtime_registers_extra_tools() {
             runner,
             permissioned_factory,
         )),
-        automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+        automatic_compaction: merry_runtime::CompactionConfig::disabled(),
         retry_policy: None,
         context_compaction: None,
         approval_review: None,

crates/merry-cli/src/coding/tests/project_rules.rs

@@ -36,7 +36,7 @@ async fn coding_projects_root_agents_in_the_stable_prefix() {
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),
@@ -89,7 +89,7 @@ async fn coding_omits_project_rules_when_root_agents_is_missing() {
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),

crates/merry-cli/src/coding/tests/skills.rs

@@ -35,7 +35,7 @@ async fn projects_skill_metadata_without_body() {
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),
@@ -110,7 +110,7 @@ async fn includes_skill_roots_in_workspace_read_tools() {
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),
@@ -155,7 +155,7 @@ async fn allows_missing_default_skill_root() {
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),

crates/merry-cli/src/coding/tests/subagents.rs

@@ -31,7 +31,7 @@ async fn hides_subagent_tools_by_default() {
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),
@@ -78,7 +78,7 @@ async fn exposes_subagent_tools_when_enabled() {
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),
@@ -176,7 +176,7 @@ async fn subagent_with_narrow_tools_keeps_stable_profile_and_runtime_admission()
         model_name(),
         CodingRuntimeOptions {
             approval_review: None,
-            automatic_compaction: merry_runtime::AutomaticCompactionConfig::disabled(),
+            automatic_compaction: merry_runtime::CompactionConfig::disabled(),
             retry_policy: None,
             context_compaction: None,
             process_backend: test_process_backend(),

crates/merry-cli/src/config/provider.rs

@@ -62,8 +62,10 @@ impl MerryConfig {
         } else {
             ProviderConfigSource::User
         };
-        let reasoning_effort =
-            parse_provider_reasoning_effort(alias.as_str(), provider.reasoning_effort.as_deref())?;
+        let reasoning_effort = parse_reasoning_effort(
+            &format!("providers.{alias}.reasoning_effort"),
+            provider.reasoning_effort.as_deref(),
+        )?;
         let service_tier =
             parse_provider_service_tier(alias.as_str(), provider.service_tier.as_deref())?;
         let protocol = match kind {
@@ -109,13 +111,11 @@ impl MerryConfig {
             .and_then(|providers| providers.default.as_ref())
             .filter(|default| default.provider == alias)
             .and_then(|default| default.reasoning_effort.as_deref())
-            .map(ReasoningEffort::new)
-            .transpose()
-            .map_err(|error| {
-                ConfigError::Invalid(format!(
-                    "providers.default.reasoning_effort is invalid: {error}"
-                ))
-            })?;
+            .map(|effort| {
+                parse_reasoning_effort("providers.default.reasoning_effort", Some(effort))
+            })
+            .transpose()?
+            .flatten();
 
         match default_reasoning_effort {
             Some(reasoning_effort) => Ok(Some(reasoning_effort)),
@@ -246,8 +246,10 @@ impl MerryConfig {
             .ok_or_else(|| ConfigError::Invalid(format!("[providers.{alias}] is required")))?;
         let kind = provider.kind.as_deref().unwrap_or(alias);
         let api_key = resolve_api_key_source(alias, provider, &self.config_dir, &self.home)?;
-        let reasoning_effort =
-            parse_provider_reasoning_effort(alias, provider.reasoning_effort.as_deref())?;
+        let reasoning_effort = parse_reasoning_effort(
+            &format!("providers.{alias}.reasoning_effort"),
+            provider.reasoning_effort.as_deref(),
+        )?;
         let service_tier = parse_provider_service_tier(alias, provider.service_tier.as_deref())?;
         let protocol = provider.protocol.unwrap_or_default();
         match kind {
@@ -359,18 +361,19 @@ fn resolve_api_key_source(
     Ok(api_key)
 }
 
-fn parse_provider_reasoning_effort(
-    alias: &str,
+/// Parses one reasoning-effort config value under its own config path.
+///
+/// Every place that accepts a reasoning-effort string shares this, so the
+/// accepted values and the diagnostic shape stay identical for providers,
+/// provider defaults, and runtime compaction.
+pub(super) fn parse_reasoning_effort(
+    field: &str,
     value: Option<&str>,
 ) -> Result<Option<ReasoningEffort>, ConfigError> {
     value
         .map(ReasoningEffort::new)
         .transpose()
-        .map_err(|error| {
-            ConfigError::Invalid(format!(
-                "providers.{alias}.reasoning_effort is invalid: {error}"
-            ))
-        })
+        .map_err(|error| ConfigError::Invalid(format!("{field} is invalid: {error}")))
 }
 
 fn parse_provider_service_tier(