feat: knowledge base for long-term memory (#1099) by bitloi · Pull Request #1115 · eigent-ai/eigent

bitloi · 2026-02-01T02:17:49Z

Description

Implements knowledge base for long-term memory (closes #1099).

What this PR does:

Storage: SQLite-backed knowledge store per project (file_save_path/.eigent_knowledge/ or ~/.eigent). Table: project_id, content, created_at. Data persists across sessions.
Ingestion: (1) REST API: POST /knowledge with project_id and content. (2) remember_this tool for the developer agent (and custom agents via knowledge_base_toolkit) so the assistant can save facts when the user asks.
Retrieval: Keyword filter via LIKE; get_context_for_prompt(project_id, query=...) builds a formatted string (max 4000 chars, 20 entries) for injection into prompts.
Integration: build_conversation_context() prepends knowledge base context when building prompts. Used for simple-question answers, multi-turn simple path, question_confirm, and workforce context. Optional query (user question) filters relevant entries when available.
REST API: GET /knowledge?project_id=...&query=...&limit=50, DELETE /knowledge/{id}?project_id=....
Tests: Unit tests for add/get/delete, keyword query, context formatting, wrong-project no-op, and TestClient API test for POST/GET/DELETE.

No frontend changes; backend-only. Users can add entries via API (e.g. curl) or by asking the developer agent to remember something; retrieved KB is injected into chat context automatically.

What is the purpose of this pull request?

Bug fix
New Feature
Documentation update
Other

- Add SQLite-backed knowledge store (backend/app/utils/knowledge_base.py) with add_entry, get_entries, delete_entry, get_context_for_prompt - Inject KB context into chat prompts via build_conversation_context (query-scoped retrieval when user question is available) - Add REST API: POST/GET/DELETE /knowledge (knowledge_controller) - Add remember_this tool (KnowledgeBaseToolkit) for developer agent to save facts to the project KB; register in get_toolkits for custom agents - Developer system message: use remember_this for important facts/decisions

…PI tests - knowledge_base: use os.environ.get instead of app.component.environment.env so tests run from backend/ without repo-root utils - tests: add test_knowledge_base.py (add/get/delete, query filter, context, wrong project no-op) and TestClient API test (POST/GET/DELETE /knowledge)

- Resolve router.py: use main's logging, add knowledge_controller - Accept deletion of backend/app/utils/agent.py (agent code moved to app/agent/) - Add knowledge base to new agent module: KnowledgeBaseToolkit in tools.py, developer.py (toolkit + tools + tool_names), remember_this in DEVELOPER_SYS_PROMPT

- Rebase KB changes onto upstream main chat_service: add get_knowledge_context import, query param and KB block in build_conversation_context, pass query= at simple-question, multi-turn simple, and question_confirm call sites

- router.py: align with main style (single-line imports/config), keep knowledge_controller - chat_service.py: add ActionTimeoutData import for main compatibility, keep knowledge base

bitloi · 2026-02-04T18:40:51Z

@a7m-1st @4pmtong @Wendong-Fan Please review my pr.

bytecii

Thanks for contribution. Left some comments.

backend/app/agent/factory/developer.py

backend/app/utils/toolkit/knowledge_base_toolkit.py

backend/app/utils/knowledge_base.py

backend/app/utils/sqlite_toolkit.py

backend/app/agent/prompt.py

backend/app/utils/sqlite_toolkit.py

bitloi · 2026-02-04T21:45:43Z

@bytecii I just fixed the issues you mentioned, would you please review the updates again?

bytecii · 2026-02-04T21:55:17Z

@bitloi I don't think they are fixed

…y, remove remember_this prompt, ruff lint

bitloi · 2026-02-04T22:04:40Z

@bitloi I don't think they are fixed

Sorry for the mistake, I didn't push the changes.

bitloi · 2026-02-05T14:50:47Z

@Wendong-Fan Would you please check the pr?

bitloi · 2026-02-08T00:46:06Z

Thanks @bitloi for working on this feature! Long-term memory is a valuable addition. However, I would second @nitpicker55555 's concerns about the current design approach. SQLite may be too complex and introduce more cost for this use case, a simple .md file would be more appropriate than a database, in camel we also supported skills which would make using .md file system more suitable

the current design's reading would automatically injected into prompts but for writing it will require explicit toolkit call, this inconsistency is confusing. If we use a file like .eigent/memory.md, agents can do both reading and writing.

now the sqlite_toolkit.py is not a Toolkit (doesn't extend BaseToolkit), it's a data access layer. which adds to the confusion around its role and responsibilities

I’d strongly suggest implementing long-term memory using a markdown-based file system for now. Happy to discuss this further and iterate together.

@Wendong-Fan, thanks for the review! I made the changes you suggested - switched from SQLite to a simple markdown file at .eigent/memory.md. Much cleaner now. The toolkit has both read and write tools, and I removed the REST API since it's not needed anymore. Tests are all green. Let me know if anything else needs tweaking!

Wendong-Fan · 2026-02-08T18:07:28Z

Thanks @bitloi for working on this feature! Long-term memory is a valuable addition. However, I would second @nitpicker55555 's concerns about the current design approach. SQLite may be too complex and introduce more cost for this use case, a simple .md file would be more appropriate than a database, in camel we also supported skills which would make using .md file system more suitable
the current design's reading would automatically injected into prompts but for writing it will require explicit toolkit call, this inconsistency is confusing. If we use a file like .eigent/memory.md, agents can do both reading and writing.
now the sqlite_toolkit.py is not a Toolkit (doesn't extend BaseToolkit), it's a data access layer. which adds to the confusion around its role and responsibilities
I’d strongly suggest implementing long-term memory using a markdown-based file system for now. Happy to discuss this further and iterate together.

@Wendong-Fan, thanks for the review! I made the changes you suggested - switched from SQLite to a simple markdown file at .eigent/memory.md. Much cleaner now. The toolkit has both read and write tools, and I removed the REST API since it's not needed anymore. Tests are all green. Let me know if anything else needs tweaking!

thanks @bitloi for the update!

backend/app/utils/memory_file.py

…dback) - memory_file: get_context_for_prompt -> get_index_for_prompt (first max_lines; cap at _MAX_INDEX_LINES); add MEMORY_ARCHITECTURE_PROMPT - knowledge_base_toolkit: remove remember_this/read_project_memory; agent uses file ops on .eigent/*.md; get_tools() returns [] - Validation, error handling, and tests updated for index-based design

…oi/eigent into feature/knowledge-base-1099

backend/app/utils/memory_file.py

backend/app/utils/long_term_memory.py

backend/app/agent/toolkit/knowledge_base_toolkit.py

backend/pyproject.toml

…mpt, doc toolkit - memory_file: remove append_memory, write_memory (unused in production); keep read_memory, get_index_for_prompt - chat_service: when knowledge_base_toolkit in data.tools, inject MEMORY_ARCHITECTURE_PROMPT and get_index_for_prompt(working_directory) into system prompt - knowledge_base_toolkit: doc why toolkit has no tools (signal for chat_service to inject memory prompt) - tests: use _write_memory helper instead of removed append/write_memory

bitloi · 2026-02-09T13:22:09Z

@nitpicker55555 I fixed them. Would you mind reviewing it?

backend/app/agent/toolkit/knowledge_base_toolkit.py

backend/app/service/chat_service.py

backend/uv.lock

- Remove KnowledgeBaseToolkit; add use_project_memory to NewAgent and ActionNewAgent - chat_service injects memory prompt when use_project_memory is true - Revert build_conversation_context to single-line args (no linter-only changes) - Regenerate uv.lock without ruff - Update tests: drop toolkit tests, keep memory_file tests

…oi/eigent into feature/knowledge-base-1099

bitloi · 2026-02-09T18:33:17Z

@nitpicker55555 Can you check the changes again?

nitpicker55555 · 2026-02-09T18:52:31Z

@bitloi backend/app/router.py changes are still only linter changes. Please remove these linter changes

@Wendong-Fan what do you think of the current design?

bitloi · 2026-02-09T19:12:57Z

@bitloi backend/app/router.py changes are still only linter changes. Please remove these linter changes

@Wendong-Fan what do you think of the current design?

@nitpicker55555 Fixed it.

backend/tests/app/utils/test_long_term_memory.py

backend/app/utils/long_term_memory.py

backend/app/utils/memory_file.py

backend/app/service/chat_service.py

backend/app/model/chat.py

…ory, move tests, add continuation note - Rename memory_file.py to long_term_memory.py and update logger/imports - Rename use_project_memory to use_long_term_memory (NewAgent, ActionNewAgent, chat_service) - Add remaining line count to truncation note in get_index_for_prompt - Move tests to backend/tests/app/utils/test_long_term_memory.py - Add comment that memory index is snapshot at agent-creation time

bitloi · 2026-02-15T04:45:43Z

@bytecii Ready for review!

bitloi and others added 15 commits February 1, 2026 02:49

Merge upstream/main, resolve chat_service.py (keep KB integration)

852ab43

Merge branch 'main' into feature/knowledge-base-1099

f678309

Merge branch 'main' into feature/knowledge-base-1099

3b9c0e4

Merge branch 'main' into feature/knowledge-base-1099

3d10e6d

Merge branch 'main' into feature/knowledge-base-1099

47f4f10

Merge branch 'main' into feature/knowledge-base-1099

fbd480b

Merge branch 'main' into feature/knowledge-base-1099

b7af46a

fix: resolve merge conflicts with main (router.py, chat_service.py)

7216ce8

- router.py: align with main style (single-line imports/config), keep knowledge_controller - chat_service.py: add ActionTimeoutData import for main compatibility, keep knowledge base

Merge upstream/main into feature/knowledge-base-1099, resolve conflicts

4e2dcb2

Merge branch 'main' into feature/knowledge-base-1099

c363187

Merge branch 'main' into feature/knowledge-base-1099

3d2f4b6

bytecii reviewed Feb 4, 2026

View reviewed changes

Merge branch 'main' into feature/knowledge-base-1099

d328676

bitloi added 2 commits February 4, 2026 23:04

PR feedback: rename to sqlite_toolkit, FTS5/BM25 search, add tool onl…

b2fd959

…y, remove remember_this prompt, ruff lint

Remove knowledge base from developer agent for now (per review)

70cd6df

Merge branch 'main' into feature/knowledge-base-1099

b4bfc4e

bitloi requested a review from bytecii February 4, 2026 22:34

Merge branch 'main' into feature/knowledge-base-1099

e195c47

bitloi and others added 3 commits February 5, 2026 15:17

Merge branch 'main' into feature/knowledge-base-1099

dd804f2

Merge branch 'main' into feature/knowledge-base-1099

606533f

Merge branch 'main' into feature/knowledge-base-1099

06d19b1

bitloi requested a review from Wendong-Fan February 8, 2026 00:46

Wendong-Fan modified the milestones: Sprint 13, Sprint 14 Feb 8, 2026

Merge branch 'main' into feature/knowledge-base-1099

60367cb

nitpicker55555 reviewed Feb 9, 2026

View reviewed changes

backend/app/utils/memory_file.py Outdated Show resolved Hide resolved

bitloi added 2 commits February 9, 2026 02:01

Merge branch 'feature/knowledge-base-1099' of https://github.com/bitl…

3bd0880

…oi/eigent into feature/knowledge-base-1099

bitloi requested a review from nitpicker55555 February 9, 2026 01:07

nitpicker55555 reviewed Feb 9, 2026

View reviewed changes

backend/app/utils/memory_file.py Outdated Show resolved Hide resolved

backend/app/utils/long_term_memory.py Show resolved Hide resolved

backend/app/agent/toolkit/knowledge_base_toolkit.py Outdated Show resolved Hide resolved

backend/pyproject.toml Show resolved Hide resolved

bitloi added 2 commits February 9, 2026 12:25

chore(backend): remove ruff from dev dependencies

4cbdaf2

bitloi requested a review from nitpicker55555 February 9, 2026 11:29

Merge branch 'main' into feature/knowledge-base-1099

7e7991e

nitpicker55555 reviewed Feb 9, 2026

View reviewed changes

backend/app/agent/toolkit/knowledge_base_toolkit.py Outdated Show resolved Hide resolved

nitpicker55555 reviewed Feb 9, 2026

View reviewed changes

backend/app/service/chat_service.py Show resolved Hide resolved

backend/uv.lock Show resolved Hide resolved

bitloi added 2 commits February 9, 2026 19:30

Merge branch 'feature/knowledge-base-1099' of https://github.com/bitl…

d000b44

…oi/eigent into feature/knowledge-base-1099

bitloi requested a review from nitpicker55555 February 9, 2026 18:49

Revert linter-only changes in router.py (review feedback)

dafac62

bytecii reviewed Feb 10, 2026

View reviewed changes

bitloi and others added 2 commits February 14, 2026 20:58

Merge branch 'main' into feature/knowledge-base-1099

f63ba1a

Merge branch 'main' into feature/knowledge-base-1099

d3c9b98

Conversation

bitloi commented Feb 1, 2026

Description

What is the purpose of this pull request?

Uh oh!

bitloi commented Feb 4, 2026

Uh oh!

bytecii left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

bitloi commented Feb 4, 2026

Uh oh!

bytecii commented Feb 4, 2026

Uh oh!

bitloi commented Feb 4, 2026

Uh oh!

bitloi commented Feb 5, 2026

Uh oh!

bitloi commented Feb 8, 2026

Uh oh!

Wendong-Fan commented Feb 8, 2026

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

bitloi commented Feb 9, 2026

Uh oh!

Uh oh!

Uh oh!

Uh oh!

bitloi commented Feb 9, 2026

Uh oh!

nitpicker55555 commented Feb 9, 2026

Uh oh!

bitloi commented Feb 9, 2026

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Uh oh!

bitloi commented Feb 15, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants