CodebuffAI · jahooma · May 6, 2026
@@ -0,0 +1,29 @@
+import { describe, expect, test } from 'bun:test'
+
+import { FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID } from '@codebuff/common/constants/freebuff-models'
+
+import { createBase2 } from '../base2/base2'
+
+describe('base2 free reviewer selection', () => {
+  test('uses the DeepSeek reviewer when free mode uses DeepSeek V4 Pro', () => {
+    const base2 = createBase2('free', {
+      model: FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID,
+    })
+
+    expect(base2.spawnableAgents).toContain('code-reviewer-deepseek')
+    expect(base2.spawnableAgents).not.toContain('code-reviewer-lite')
+    expect(base2.instructionsPrompt).toContain('code-reviewer-deepseek')
+    expect(base2.stepPrompt).toContain('code-reviewer-deepseek')
+  })
+
+  test('keeps the lite reviewer for other free-mode models', () => {
+    const base2 = createBase2('free', {
+      model: 'moonshotai/kimi-k2.6',
+    })
+
+    expect(base2.spawnableAgents).toContain('code-reviewer-lite')
+    expect(base2.spawnableAgents).not.toContain('code-reviewer-deepseek')
+    expect(base2.instructionsPrompt).toContain('code-reviewer-lite')
+    expect(base2.stepPrompt).toContain('code-reviewer-lite')
+  })
+})
@@ -324,6 +324,27 @@ describe('context-pruner handleSteps', () => {
     expect(content).toContain('edited file: file1.ts')
   })
 
+  test('includes inspected path for single read calls', () => {
+    const messages = [
+      createMessage('user', 'Read one file'),
+      createToolCallMessage('call-1', 'read', {
+        path: 'src/index.ts',
+        offset: 25,
+        limit: 50,
+      }),
+      createToolResultMessage('call-1', 'read', {
+        path: 'src/index.ts',
+        content: 'file data',
+      }),
+    ]
+
+    const results = runHandleSteps(messages, 50000, 10000)
+    const content = results[0].input.messages[0].content[0].text
+
+    expect(content).toContain('inspected file: src/index.ts')
+    expect(content).not.toContain('used tool read')
+  })
+
   test('summarizes various tool types correctly', () => {
     const messages = [
       createMessage('user', 'Do various tasks'),

@@ -15,7 +15,7 @@ function buildDeepSystemPrompt(noAskUser: boolean, noLearning: boolean): string
 - **Understand first, act second:** Always gather context and read relevant files BEFORE editing files.
 - **Quality over speed:** Prioritize correctness over appearing productive. Fewer, well-informed agents are better than many rushed ones.
 - **Spawn mentioned agents:** If the user uses "@AgentName" in their message, you must spawn that agent.
-- **Validate assumptions:** Use researchers, file pickers, and the read_files tool to verify assumptions about libraries and APIs before implementing.
+- **Validate assumptions:** Use researchers, file pickers, and the read tool to verify assumptions about libraries and APIs before implementing.
 - **Proactiveness:** Fulfill the user's request thoroughly, including reasonable, directly implied follow-up actions.
 - **Confirm Ambiguity/Expansion:** Do not take significant actions beyond the clear scope of the request without confirming with the user. If asked *how* to do something, explain first, don't just do it.${noAskUser ? '' : `
 - **Ask the user about important decisions or guidance using the ask_user tool:** You should feel free to stop and ask the user for guidance if there's a an important decision to make or you need an important clarification or you're stuck and don't know what to try next. Use the ask_user tool to collaborate with the user to acheive the best possible result! Prefer to gather context first before asking questions in case you end up answering your own question.`}
@@ -129,7 +129,7 @@ Update these as you complete each step during implementation.
 Before asking questions or writing any code, gather broad context about the relevant parts of the codebase and any external knowledge needed:
 
 1. Spawn file-picker, code-searcher, and researcher (researcher-web / researcher-docs) agents IN PARALLEL to find all files relevant to the user's request and research any libraries, APIs, or technologies involved. Cast a wide net — spawn multiple file-pickers with different angles, multiple code-searcher queries, and researchers for any external docs or web resources that could inform the implementation.
-2. Read the relevant files returned by these agents using read_files. Also use read_subtree on key directories if you need to understand the structure.
+2. Read the relevant files returned by these agents using read. Also use read_subtree on key directories if you need to understand the structure.
 3. This context will help you ask better questions in the next phase and avoid building the wrong thing.
 
 ## Phase 2 — Spec
@@ -281,7 +281,7 @@ export function createBaseDeep(options?: {
     includeMessageHistory: true,
     toolNames: buildArray(
       'spawn_agents',
-      'read_files',
+      'read',
       'read_subtree',
       !noAskUser && 'suggest_followups',
       'apply_patch',

@@ -5,6 +5,7 @@ import {
   FREEBUFF_GEMINI_THINKER_STEP_PROMPT,
   FREEBUFF_GEMINI_THINKER_SYSTEM_INSTRUCTION,
 } from '@codebuff/common/constants/freebuff-gemini-thinker'
+import { FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID } from '@codebuff/common/constants/freebuff-models'
 
 import { publisher } from '../constants'
 import {
@@ -45,8 +46,12 @@ export function createBase2(
     (mode === 'lite'
       ? 'moonshotai/kimi-k2.6'
       : mode === 'free'
-        ? 'deepseek/deepseek-v4-pro'
+        ? FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID
         : 'anthropic/claude-opus-4.7')
+  const freeCodeReviewerAgent =
+    model === FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID
+      ? 'code-reviewer-deepseek'
+      : 'code-reviewer-lite'
   // Bundled free-mode definitions ship with the gemini-thinker spawnable +
   // prompts; the CLI strips them at runtime if the user picks a fast model
   // that doesn't benefit (e.g. MiniMax). Smart freebuff models (Kimi,
@@ -86,7 +91,7 @@ export function createBase2(
     includeMessageHistory: true,
     toolNames: buildArray(
       'spawn_agents',
-      'read_files',
+      'read',
       'read_subtree',
       !isFast && 'write_todos',
       !isFast && !noAskUser && 'suggest_followups',
@@ -114,7 +119,7 @@ export function createBase2(
       isMax && 'editor-multi-prompt',
       'tmux-cli',
       'browser-use',
-      isFree && 'code-reviewer-lite',
+      isFree && freeCodeReviewerAgent,
       isDefault && 'code-reviewer',
       isMax && 'code-reviewer-multi-prompt',
       hasFreeGeminiThinker && FREEBUFF_GEMINI_THINKER_AGENT_ID,
@@ -130,7 +135,7 @@ export function createBase2(
 - **Understand first, act second:** Always gather context and read relevant files BEFORE editing files.
 - **Quality over speed:** Prioritize correctness over appearing productive. Fewer, well-informed agents are better than many rushed ones.
 - **Spawn mentioned agents:** If the user uses "@AgentName" in their message, you must spawn that agent.
-- **Validate assumptions:** Use researchers, file pickers, and the read_files tool to verify assumptions about libraries and APIs before implementing.
+- **Validate assumptions:** Use researchers, file pickers, and the read tool to verify assumptions about libraries and APIs before implementing.
 - **Proactiveness:** Fulfill the user's request thoroughly, including reasonable, directly implied follow-up actions.
 - **Confirm Ambiguity/Expansion:** Do not take significant actions beyond the clear scope of the request without confirming with the user. If asked *how* to do something, explain first, don't just do it.${
       noAskUser
@@ -183,7 +188,7 @@ Use the spawn_agents tool to spawn specialized agents to help you complete the u
     isMax &&
       `- IMPORTANT: You must spawn the editor-multi-prompt agent to implement the changes after you have gathered all the context you need. You must spawn this agent for non-trivial changes, since it writes much better code than you would with the str_replace or write_file tools. Don't spawn the editor in parallel with context-gathering agents.`,
     isFree &&
-      '- Spawn a code-reviewer-lite to review the changes after you have implemented the changes.',
+      `- Spawn a ${freeCodeReviewerAgent} to review the changes after you have implemented the changes.`,
     '- Spawn bashers sequentially if the second command depends on the the first.',
     isDefault &&
       '- Spawn a code-reviewer to review the changes after you have implemented the changes.',
@@ -231,11 +236,11 @@ ${buildArray(
 <response>
 [ You spawn 3 file-pickers, 2 code-searchers, and a docs researcher in parallel to find relevant files and do research online. You use the list_directory and glob tools directly to search the codebase. ]
 
-[ You read a few of the relevant files using the read_files tool in two separate tool calls ]
+[ You read a few of the relevant files using the read tool in separate tool calls ]
 
 [ You spawn another file-picker and code-searcher to find more relevant files, and use glob tools ]
 
-[ You read a few other relevant files using the read_files tool ]${
+[ You read a few other relevant files using the read tool ]${
       !noAskUser
         ? `\n\n[ You ask the user for important clarifications on their request or alternate implementation strategies using the ask_user tool ]`
         : ''
@@ -252,7 +257,7 @@ ${
   isDefault
     ? `[ You spawn a code-reviewer, a basher to typecheck the changes, and another basher to run tests, all in parallel ]`
     : isFree
-      ? `[ You spawn a code-reviewer-lite to review the changes, a basher to typecheck the local changes, a basher to typecheck the whole project, and another basher to run tests, all in parallel ]`
+      ? `[ You spawn a ${freeCodeReviewerAgent} to review the changes, a basher to typecheck the local changes, a basher to typecheck the whole project, and another basher to run tests, all in parallel ]`
       : isMax
         ? `[  You spawn a basher to typecheck the changes, and another basher to run tests, in parallel. Then, you spawn a code-reviewer-multi-prompt to review the changes. ]`
         : '[ You spawn a basher to typecheck the changes and another basher to run tests, all in parallel ]'
@@ -262,7 +267,7 @@ ${
   isDefault
     ? `[ You fix the issues found by the code-reviewer and type/test errors ]`
     : isFree
-      ? `[ You fix the issues found by the code-reviewer-lite and type/test errors ]`
+      ? `[ You fix the issues found by the ${freeCodeReviewerAgent} and type/test errors ]`
       : isMax
         ? `[ You fix the issues found by the code-reviewer-multi-prompt and type/test errors ]`
         : '[ You fix the issues found by the type/test errors and spawn more bashers to confirm ]'
@@ -302,6 +307,7 @@ ${PLACEHOLDER.GIT_CHANGES_PROMPT}
           isDefault,
           isMax,
           isFree,
+          freeCodeReviewerAgent,
           hasFreeGeminiThinker,
           hasNoValidation,
           noAskUser,
@@ -315,6 +321,7 @@ ${PLACEHOLDER.GIT_CHANGES_PROMPT}
           hasNoValidation,
           isSonnet,
           isFree,
+          freeCodeReviewerAgent,
           hasFreeGeminiThinker,
           noAskUser,
         }),
@@ -356,14 +363,15 @@ ${PLACEHOLDER.GIT_CHANGES_PROMPT}
   }
 }
 
-const EXPLORE_PROMPT = `- Iteratively spawn file pickers, code searchers, bashers, and web/docs researchers to gather context as needed. Use the list_directory and glob tools directly for searching and exploring the codebase. The file-picker and code-searcher agents are very useful to find relevant files -- try spawning multiple in parallel (say, 2-5 file-pickers and 1-3 code-searchers) to explore different parts of the codebase. Use read_subtree if you need to grok a particular part of the codebase. Read all the relevant files using the read_files tool.`
+const EXPLORE_PROMPT = `- Iteratively spawn file pickers, code searchers, bashers, and web/docs researchers to gather context as needed. Use the list_directory and glob tools directly for searching and exploring the codebase. The file-picker and code-searcher agents are very useful to find relevant files -- try spawning multiple in parallel (say, 2-5 file-pickers and 1-3 code-searchers) to explore different parts of the codebase. Use read_subtree if you need to grok a particular part of the codebase. Read relevant files using the read tool.`
 
 function buildImplementationInstructionsPrompt({
   isSonnet,
   isFast,
   isDefault,
   isMax,
   isFree,
+  freeCodeReviewerAgent,
   hasFreeGeminiThinker,
   hasNoValidation,
   noAskUser,
@@ -373,6 +381,7 @@ function buildImplementationInstructionsPrompt({
   isDefault: boolean
   isMax: boolean
   isFree: boolean
+  freeCodeReviewerAgent: string
   hasFreeGeminiThinker: boolean
   hasNoValidation: boolean
   noAskUser: boolean
@@ -407,7 +416,7 @@ ${buildArray(
   (isDefault || isMax) &&
     `- Spawn a ${isDefault ? 'code-reviewer' : 'code-reviewer-multi-prompt'} to review the changes after you have implemented changes. (Skip this step only if the change is extremely straightforward and obvious.)`,
   isFree &&
-    `- Spawn a code-reviewer-lite to review the changes after you have implemented changes. (Skip this step only if the change is extremely straightforward and obvious.)`,
+    `- Spawn a ${freeCodeReviewerAgent} to review the changes after you have implemented changes. (Skip this step only if the change is extremely straightforward and obvious.)`,
   `- Inform the user that you have completed the task in one sentence or a few short bullet points.${isSonnet ? " Don't create any markdown summary files or example documentation files, unless asked by the user." : ''}`,
   !isFast &&
     !noAskUser &&
@@ -422,6 +431,7 @@ function buildImplementationStepPrompt({
   hasNoValidation,
   isSonnet,
   isFree,
+  freeCodeReviewerAgent,
   hasFreeGeminiThinker,
   noAskUser,
 }: {
@@ -431,6 +441,7 @@ function buildImplementationStepPrompt({
   hasNoValidation: boolean
   isSonnet: boolean
   isFree: boolean
+  freeCodeReviewerAgent: string
   hasFreeGeminiThinker: boolean
   noAskUser: boolean
 }) {
@@ -444,7 +455,7 @@ function buildImplementationStepPrompt({
     (isDefault || isMax) &&
       `You must spawn a ${isDefault ? 'code-reviewer' : 'code-reviewer-multi-prompt'} to review the changes after you have implemented the changes and in parallel with typechecking or testing.`,
     isFree &&
-      `You must spawn a code-reviewer-lite to review the changes after you have implemented the changes and in parallel with typechecking or testing.`,
+      `You must spawn a ${freeCodeReviewerAgent} to review the changes after you have implemented the changes and in parallel with typechecking or testing.`,
     `After completing the user request, summarize your changes in a sentence${isFast ? '' : ' or a few short bullet points'}.${isSonnet ? " Don't create any summary markdown files or example documentation files, unless asked by the user." : ''}.`,
     !isFast &&
       !noAskUser &&

@@ -141,6 +141,10 @@ const definition: AgentDefinition = {
           }
           return 'inspected files'
         }
+        case 'read': {
+          const path = input.path as string | undefined
+          return path ? `inspected file: ${path}` : 'inspected a file'
+        }
         case 'write_file': {
           const path = input.path as string | undefined
           return path ? `wrote file: ${path}` : 'wrote a file'

@@ -61,6 +61,7 @@ export const createGeneralAgent = (options: {
     ),
     toolNames: [
       'spawn_agents',
+      'read',
       'read_files',
       'read_subtree',
       'str_replace',

@@ -0,0 +1,13 @@
+import { FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID } from '@codebuff/common/constants/freebuff-models'
+
+import { publisher } from '../constants'
+import type { SecretAgentDefinition } from '../types/secret-agent-definition'
+import { createReviewer } from './code-reviewer'
+
+const definition: SecretAgentDefinition = {
+  id: 'code-reviewer-deepseek',
+  publisher,
+  ...createReviewer(FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID),
+}
+
+export default definition
@@ -14,6 +14,7 @@ export type ToolName =
   | 'lookup_agent_info'
   | 'propose_str_replace'
   | 'propose_write_file'
+  | 'read'
   | 'read_docs'
   | 'read_files'
   | 'read_subtree'
@@ -48,6 +49,7 @@ export interface ToolParamsMap {
   lookup_agent_info: LookupAgentInfoParams
   propose_str_replace: ProposeStrReplaceParams
   propose_write_file: ProposeWriteFileParams
+  read: ReadParams
   read_docs: ReadDocsParams
   read_files: ReadFilesParams
   read_subtree: ReadSubtreeParams
@@ -258,6 +260,18 @@ export interface ReadDocsParams {
   max_tokens?: number
 }
 
+/**
+ * Read the contents of a single text file. Use offset and limit for large files.
+ */
+export interface ReadParams {
+  /** Path to the file to read, relative to the project root or absolute within the project. */
+  path: string
+  /** Line number to start reading from (1-indexed). */
+  offset?: number
+  /** Maximum number of lines to read. */
+  limit?: number
+}
+
 /**
  * Read the multiple files from disk and return their contents. Use this tool to read as many files as would be helpful to answer the user's request.
  */

@@ -1,6 +1,9 @@
 import { describe, expect, test } from 'bun:test'
 
-import { FREEBUFF_GEMINI_PRO_MODEL_ID } from '../constants/freebuff-models'
+import {
+  FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID,
+  FREEBUFF_GEMINI_PRO_MODEL_ID,
+} from '../constants/freebuff-models'
 import { FREEBUFF_GEMINI_THINKER_AGENT_ID } from '../constants/freebuff-gemini-thinker'
 import {
   isFreebuffGeminiThinkerAgent,
@@ -44,4 +47,19 @@ describe('free mode agent model allowlist', () => {
       ),
     ).toBe(false)
   })
+
+  test('allows the DeepSeek reviewer only with DeepSeek V4 Pro', () => {
+    expect(
+      isFreeModeAllowedAgentModel(
+        'code-reviewer-deepseek',
+        FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID,
+      ),
+    ).toBe(true)
+    expect(
+      isFreeModeAllowedAgentModel(
+        'code-reviewer-deepseek',
+        FREEBUFF_GEMINI_PRO_MODEL_ID,
+      ),
+    ).toBe(false)
+  })
 })
@@ -65,6 +65,7 @@ export const FREE_MODE_AGENT_MODELS: Record<string, Set<string>> = {
 
   // Code reviewer for free mode
   'code-reviewer-lite': new Set(FREEBUFF_ALLOWED_MODEL_IDS),
+  'code-reviewer-deepseek': new Set([FREEBUFF_DEEPSEEK_V4_PRO_MODEL_ID]),
 
   // Legacy: kept for the standalone gemini thinker agent if invoked directly.
   [FREEBUFF_GEMINI_THINKER_AGENT_ID]: new Set([FREEBUFF_GEMINI_PRO_MODEL_ID]),

@@ -14,6 +14,7 @@ export type ToolName =
   | 'lookup_agent_info'
   | 'propose_str_replace'
   | 'propose_write_file'
+  | 'read'
   | 'read_docs'
   | 'read_files'
   | 'read_subtree'
@@ -48,6 +49,7 @@ export interface ToolParamsMap {
   lookup_agent_info: LookupAgentInfoParams
   propose_str_replace: ProposeStrReplaceParams
   propose_write_file: ProposeWriteFileParams
+  read: ReadParams
   read_docs: ReadDocsParams
   read_files: ReadFilesParams
   read_subtree: ReadSubtreeParams
@@ -258,6 +260,18 @@ export interface ReadDocsParams {
   max_tokens?: number
 }
 
+/**
+ * Read the contents of a single text file. Use offset and limit for large files.
+ */
+export interface ReadParams {
+  /** Path to the file to read, relative to the project root or absolute within the project. */
+  path: string
+  /** Line number to start reading from (1-indexed). */
+  offset?: number
+  /** Maximum number of lines to read. */
+  limit?: number
+}
+
 /**
  * Read the multiple files from disk and return their contents. Use this tool to read as many files as would be helpful to answer the user's request.
  */