fix: only register enabled prune tools

Author: Tarquinen

index.ts

@@ -50,32 +50,40 @@ const plugin: Plugin = (async (ctx) => {
             logger,
             config
         ),
-        tool: (config.strategies.discardTool.enabled || config.strategies.extractTool.enabled) ? {
-            discard: createDiscardTool({
-                client: ctx.client,
-                state,
-                logger,
-                config,
-                workingDirectory: ctx.directory
+        tool: {
+            ...(config.strategies.discardTool.enabled && {
+                discard: createDiscardTool({
+                    client: ctx.client,
+                    state,
+                    logger,
+                    config,
+                    workingDirectory: ctx.directory
+                }),
             }),
-            extract: createExtractTool({
-                client: ctx.client,
-                state,
-                logger,
-                config,
-                workingDirectory: ctx.directory
+            ...(config.strategies.extractTool.enabled && {
+                extract: createExtractTool({
+                    client: ctx.client,
+                    state,
+                    logger,
+                    config,
+                    workingDirectory: ctx.directory
+                }),
             }),
-        } : undefined,
+        },
         config: async (opencodeConfig) => {
-            // Add discard and extract to primary_tools by mutating the opencode config
+            // Add enabled tools to primary_tools by mutating the opencode config
             // This works because config is cached and passed by reference
-            if (config.strategies.discardTool.enabled || config.strategies.extractTool.enabled) {
+            const toolsToAdd: string[] = []
+            if (config.strategies.discardTool.enabled) toolsToAdd.push("discard")
+            if (config.strategies.extractTool.enabled) toolsToAdd.push("extract")
+
+            if (toolsToAdd.length > 0) {
                 const existingPrimaryTools = opencodeConfig.experimental?.primary_tools ?? []
                 opencodeConfig.experimental = {
                     ...opencodeConfig.experimental,
-                    primary_tools: [...existingPrimaryTools, "discard", "extract"],
+                    primary_tools: [...existingPrimaryTools, ...toolsToAdd],
                 }
-                logger.info("Added 'discard' and 'extract' to experimental.primary_tools via config mutation")
+                logger.info(`Added ${toolsToAdd.map(t => `'${t}'`).join(" and ")} to experimental.primary_tools via config mutation`)
             }
         },
         event: createEventHandler(ctx.client, config, state, logger, ctx.directory),

lib/messages/prune.ts

@@ -11,7 +11,7 @@ const PRUNED_TOOL_OUTPUT_REPLACEMENT = '[Output removed to save context - inform
 const getNudgeString = (config: PluginConfig): string => {
     const discardEnabled = config.strategies.discardTool.enabled
     const extractEnabled = config.strategies.extractTool.enabled
-    
+
     if (discardEnabled && extractEnabled) {
         return loadPrompt("nudge/nudge-both")
     } else if (discardEnabled) {
@@ -30,7 +30,7 @@ ${content}
 const getCooldownMessage = (config: PluginConfig): string => {
     const discardEnabled = config.strategies.discardTool.enabled
     const extractEnabled = config.strategies.extractTool.enabled
-    
+
     let toolName: string
     if (discardEnabled && extractEnabled) {
         toolName = "discard or extract tools"
@@ -39,7 +39,7 @@ const getCooldownMessage = (config: PluginConfig): string => {
     } else {
         toolName = "extract tool"
     }
-    
+
     return `<prunable-tools>
 Context management was just performed. Do not use the ${toolName} again. A fresh list will be available after your next tool use.
 </prunable-tools>`
@@ -115,6 +115,8 @@ export const insertPruneToolContext = (
         logger.debug("prunable-tools: \n" + prunableToolsList)
 
         let nudgeString = ""
+        // TODO: Using Math.min() means the lower frequency dominates when both tools are enabled.
+        // Consider using separate counters for each tool's nudge, or documenting this behavior.
         const nudgeFrequency = Math.min(
             config.strategies.discardTool.nudge.frequency,
             config.strategies.extractTool.nudge.frequency

lib/strategies/utils.ts

@@ -37,7 +37,6 @@ function estimateTokensBatch(texts: string[]): number[] {
 
 /**
  * Calculates approximate tokens saved by pruning the given tool call IDs.
- * TODO: Make it count message content that are not tool outputs. Currently it ONLY covers tool outputs and errors
  */
 export const calculateTokensSaved = (
     state: SessionState,