fix: ensure parallel tool calls dont double load AGENTS.md

4 files changed, 38 insertions, 5 deletions

diff --git a/packages/opencode/src/session/instruction.ts b/packages/opencode/src/session/instruction.ts
index d413e80f6..723439a3f 100644
--- a/packages/opencode/src/session/instruction.ts
+++ b/packages/opencode/src/session/instruction.ts
@@ -41,6 +41,32 @@ async function resolveRelative(instruction: string): Promise<string[]> {
 }
 
 export namespace InstructionPrompt {
+  const state = Instance.state(() => {
+    return {
+      claims: new Map<string, Set<string>>(),
+    }
+  })
+
+  function isClaimed(messageID: string, filepath: string) {
+    const claimed = state().claims.get(messageID)
+    if (!claimed) return false
+    return claimed.has(filepath)
+  }
+
+  function claim(messageID: string, filepath: string) {
+    const current = state()
+    let claimed = current.claims.get(messageID)
+    if (!claimed) {
+      claimed = new Set()
+      current.claims.set(messageID, claimed)
+    }
+    claimed.add(filepath)
+  }
+
+  export function clear(messageID: string) {
+    state().claims.delete(messageID)
+  }
+
   export async function systemPaths() {
     const config = await Config.get()
     const paths = new Set<string>()
@@ -137,7 +163,7 @@ export namespace InstructionPrompt {
     }
   }
 
-  export async function resolve(messages: MessageV2.WithParts[], filepath: string) {
+  export async function resolve(messages: MessageV2.WithParts[], filepath: string, messageID: string) {
     const system = await systemPaths()
     const already = loaded(messages)
     const results: { filepath: string; content: string }[] = []
@@ -147,7 +173,8 @@ export namespace InstructionPrompt {
 
     while (current.startsWith(root)) {
       const found = await find(current)
-      if (found && !system.has(found) && !already.has(found)) {
+      if (found && !system.has(found) && !already.has(found) && !isClaimed(messageID, found)) {
+        claim(messageID, found)
         const content = await Bun.file(found)
           .text()
           .catch(() => undefined)
diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
index 23ca47354..94eabdef7 100644
--- a/packages/opencode/src/session/prompt.ts
+++ b/packages/opencode/src/session/prompt.ts
@@ -551,6 +551,7 @@ export namespace SessionPrompt {
         model,
         abort,
       })
+      using _ = defer(() => InstructionPrompt.clear(processor.message.id))
 
       // Check if user explicitly invoked an agent via @ in this turn
       const lastUserMsg = msgs.findLast((m) => m.info.role === "user")
@@ -839,6 +840,7 @@ export namespace SessionPrompt {
       system: input.system,
       variant: input.variant,
     }
+    using _ = defer(() => InstructionPrompt.clear(info.id))
 
     const parts = await Promise.all(
       input.parts.map(async (part): Promise<MessageV2.Part[]> => {
diff --git a/packages/opencode/src/tool/read.ts b/packages/opencode/src/tool/read.ts
index 746e0b173..f230cdf44 100644
--- a/packages/opencode/src/tool/read.ts
+++ b/packages/opencode/src/tool/read.ts
@@ -60,7 +60,7 @@ export const ReadTool = Tool.define("read", {
       throw new Error(`File not found: ${filepath}`)
     }
 
-    const instructions = await InstructionPrompt.resolve(ctx.messages, filepath)
+    const instructions = await InstructionPrompt.resolve(ctx.messages, filepath, ctx.messageID)
 
     // Exclude SVG (XML-based) and vnd.fastbidsheet (.fbs extension, commonly FlatBuffers schema files)
     const isImage =
diff --git a/packages/opencode/test/session/instruction.test.ts b/packages/opencode/test/session/instruction.test.ts
index 2c44a266e..67719fa33 100644
--- a/packages/opencode/test/session/instruction.test.ts
+++ b/packages/opencode/test/session/instruction.test.ts
@@ -18,7 +18,7 @@ describe("InstructionPrompt.resolve", () => {
         const system = await InstructionPrompt.systemPaths()
         expect(system.has(path.join(tmp.path, "AGENTS.md"))).toBe(true)
 
-        const results = await InstructionPrompt.resolve([], path.join(tmp.path, "src", "file.ts"))
+        const results = await InstructionPrompt.resolve([], path.join(tmp.path, "src", "file.ts"), "test-message-1")
         expect(results).toEqual([])
       },
     })
@@ -37,7 +37,11 @@ describe("InstructionPrompt.resolve", () => {
         const system = await InstructionPrompt.systemPaths()
         expect(system.has(path.join(tmp.path, "subdir", "AGENTS.md"))).toBe(false)
 
-        const results = await InstructionPrompt.resolve([], path.join(tmp.path, "subdir", "nested", "file.ts"))
+        const results = await InstructionPrompt.resolve(
+          [],
+          path.join(tmp.path, "subdir", "nested", "file.ts"),
+          "test-message-2",
+        )
         expect(results.length).toBe(1)
         expect(results[0].filepath).toBe(path.join(tmp.path, "subdir", "AGENTS.md"))
       },