replace .cursorrules with the new cursor mdc files; create a script to generate/update the mdc files from the doc folder

This commit is contained in:
BO WEN
2025-04-20 16:18:34 -04:00
parent 7b97105438
commit a20827ec58
23 changed files with 2832 additions and 1664 deletions
+53
View File
@@ -0,0 +1,53 @@
---
description: Guidelines for using PocketFlow, Core Abstraction, (Advanced) Async
globs:
alwaysApply: false
---
# (Advanced) Async
**Async** Nodes implement `prep_async()`, `exec_async()`, `exec_fallback_async()`, and/or `post_async()`. This is useful for:
1. **prep_async()**: For *fetching/reading data (files, APIs, DB)* in an I/O-friendly way.
2. **exec_async()**: Typically used for async LLM calls.
3. **post_async()**: For *awaiting user feedback*, *coordinating across multi-agents* or any additional async steps after `exec_async()`.
**Note**: `AsyncNode` must be wrapped in `AsyncFlow`. `AsyncFlow` can also include regular (sync) nodes.
### Example
```python
class SummarizeThenVerify(AsyncNode):
async def prep_async(self, shared):
# Example: read a file asynchronously
doc_text = await read_file_async(shared["doc_path"])
return doc_text
async def exec_async(self, prep_res):
# Example: async LLM call
summary = await call_llm_async(f"Summarize: {prep_res}")
return summary
async def post_async(self, shared, prep_res, exec_res):
# Example: wait for user feedback
decision = await gather_user_feedback(exec_res)
if decision == "approve":
shared["summary"] = exec_res
return "approve"
return "deny"
summarize_node = SummarizeThenVerify()
final_node = Finalize()
# Define transitions
summarize_node - "approve" >> final_node
summarize_node - "deny" >> summarize_node # retry
flow = AsyncFlow(start=summarize_node)
async def main():
shared = {"doc_path": "document.txt"}
await flow.run_async(shared)
print("Final Summary:", shared.get("summary"))
asyncio.run(main())
```
+105
View File
@@ -0,0 +1,105 @@
---
description: Guidelines for using PocketFlow, Core Abstraction, Batch
globs:
alwaysApply: false
---
# Batch
**Batch** makes it easier to handle large inputs in one Node or **rerun** a Flow multiple times. Example use cases:
- **Chunk-based** processing (e.g., splitting large texts).
- **Iterative** processing over lists of input items (e.g., user queries, files, URLs).
## 1. BatchNode
A **BatchNode** extends `Node` but changes `prep()` and `exec()`:
- **`prep(shared)`**: returns an **iterable** (e.g., list, generator).
- **`exec(item)`**: called **once** per item in that iterable.
- **`post(shared, prep_res, exec_res_list)`**: after all items are processed, receives a **list** of results (`exec_res_list`) and returns an **Action**.
### Example: Summarize a Large File
```python
class MapSummaries(BatchNode):
def prep(self, shared):
# Suppose we have a big file; chunk it
content = shared["data"]
chunk_size = 10000
chunks = [content[i:i+chunk_size] for i in range(0, len(content), chunk_size)]
return chunks
def exec(self, chunk):
prompt = f"Summarize this chunk in 10 words: {chunk}"
summary = call_llm(prompt)
return summary
def post(self, shared, prep_res, exec_res_list):
combined = "\n".join(exec_res_list)
shared["summary"] = combined
return "default"
map_summaries = MapSummaries()
flow = Flow(start=map_summaries)
flow.run(shared)
```
---
## 2. BatchFlow
A **BatchFlow** runs a **Flow** multiple times, each time with different `params`. Think of it as a loop that replays the Flow for each parameter set.
### Example: Summarize Many Files
```python
class SummarizeAllFiles(BatchFlow):
def prep(self, shared):
# Return a list of param dicts (one per file)
filenames = list(shared["data"].keys()) # e.g., ["file1.txt", "file2.txt", ...]
return [{"filename": fn} for fn in filenames]
# Suppose we have a per-file Flow (e.g., load_file >> summarize >> reduce):
summarize_file = SummarizeFile(start=load_file)
# Wrap that flow into a BatchFlow:
summarize_all_files = SummarizeAllFiles(start=summarize_file)
summarize_all_files.run(shared)
```
### Under the Hood
1. `prep(shared)` returns a list of param dicts—e.g., `[{filename: "file1.txt"}, {filename: "file2.txt"}, ...]`.
2. The **BatchFlow** loops through each dict. For each one:
- It merges the dict with the BatchFlows own `params`.
- It calls `flow.run(shared)` using the merged result.
3. This means the sub-Flow is run **repeatedly**, once for every param dict.
---
## 3. Nested or Multi-Level Batches
You can nest a **BatchFlow** in another **BatchFlow**. For instance:
- **Outer** batch: returns a list of directory param dicts (e.g., `{"directory": "/pathA"}`, `{"directory": "/pathB"}`, ...).
- **Inner** batch: returning a list of per-file param dicts.
At each level, **BatchFlow** merges its own param dict with the parents. By the time you reach the **innermost** node, the final `params` is the merged result of **all** parents in the chain. This way, a nested structure can keep track of the entire context (e.g., directory + file name) at once.
```python
class FileBatchFlow(BatchFlow):
def prep(self, shared):
directory = self.params["directory"]
# e.g., files = ["file1.txt", "file2.txt", ...]
files = [f for f in os.listdir(directory) if f.endswith(".txt")]
return [{"filename": f} for f in files]
class DirectoryBatchFlow(BatchFlow):
def prep(self, shared):
directories = [ "/path/to/dirA", "/path/to/dirB"]
return [{"directory": d} for d in directories]
# MapSummaries have params like {"directory": "/path/to/dirA", "filename": "file1.txt"}
inner_flow = FileBatchFlow(start=MapSummaries())
outer_flow = DirectoryBatchFlow(start=inner_flow)
```
@@ -0,0 +1,124 @@
---
description: Guidelines for using PocketFlow, Core Abstraction, Communication
globs:
alwaysApply: false
---
# Communication
Nodes and Flows **communicate** in 2 ways:
1. **Shared Store (for almost all the cases)**
- A global data structure (often an in-mem dict) that all nodes can read ( `prep()`) and write (`post()`).
- Great for data results, large content, or anything multiple nodes need.
- You shall design the data structure and populate it ahead.
- > **Separation of Concerns:** Use `Shared Store` for almost all cases to separate *Data Schema* from *Compute Logic*! This approach is both flexible and easy to manage, resulting in more maintainable code. `Params` is more a syntax sugar for [Batch](mdc:batch.md).
{: .best-practice }
2. **Params (only for [Batch](mdc:batch.md))**
- Each node has a local, ephemeral `params` dict passed in by the **parent Flow**, used as an identifier for tasks. Parameter keys and values shall be **immutable**.
- Good for identifiers like filenames or numeric IDs, in Batch mode.
If you know memory management, think of the **Shared Store** like a **heap** (shared by all function calls), and **Params** like a **stack** (assigned by the caller).
---
## 1. Shared Store
### Overview
A shared store is typically an in-mem dictionary, like:
```python
shared = {"data": {}, "summary": {}, "config": {...}, ...}
```
It can also contain local file handlers, DB connections, or a combination for persistence. We recommend deciding the data structure or DB schema first based on your app requirements.
### Example
```python
class LoadData(Node):
def post(self, shared, prep_res, exec_res):
# We write data to shared store
shared["data"] = "Some text content"
return None
class Summarize(Node):
def prep(self, shared):
# We read data from shared store
return shared["data"]
def exec(self, prep_res):
# Call LLM to summarize
prompt = f"Summarize: {prep_res}"
summary = call_llm(prompt)
return summary
def post(self, shared, prep_res, exec_res):
# We write summary to shared store
shared["summary"] = exec_res
return "default"
load_data = LoadData()
summarize = Summarize()
load_data >> summarize
flow = Flow(start=load_data)
shared = {}
flow.run(shared)
```
Here:
- `LoadData` writes to `shared["data"]`.
- `Summarize` reads from `shared["data"]`, summarizes, and writes to `shared["summary"]`.
---
## 2. Params
**Params** let you store *per-Node* or *per-Flow* config that doesn't need to live in the shared store. They are:
- **Immutable** during a Node's run cycle (i.e., they don't change mid-`prep->exec->post`).
- **Set** via `set_params()`.
- **Cleared** and updated each time a parent Flow calls it.
> Only set the uppermost Flow params because others will be overwritten by the parent Flow.
>
> If you need to set child node params, see [Batch](mdc:batch.md).
{: .warning }
Typically, **Params** are identifiers (e.g., file name, page number). Use them to fetch the task you assigned or write to a specific part of the shared store.
### Example
```python
# 1) Create a Node that uses params
class SummarizeFile(Node):
def prep(self, shared):
# Access the node's param
filename = self.params["filename"]
return shared["data"].get(filename, "")
def exec(self, prep_res):
prompt = f"Summarize: {prep_res}"
return call_llm(prompt)
def post(self, shared, prep_res, exec_res):
filename = self.params["filename"]
shared["summary"][filename] = exec_res
return "default"
# 2) Set params
node = SummarizeFile()
# 3) Set Node params directly (for testing)
node.set_params({"filename": "doc1.txt"})
node.run(shared)
# 4) Create Flow
flow = Flow(start=node)
# 5) Set Flow params (overwrites node params)
flow.set_params({"filename": "doc2.txt"})
flow.run(shared) # The node summarizes doc2, not doc1
```
+176
View File
@@ -0,0 +1,176 @@
---
description: Guidelines for using PocketFlow, Core Abstraction, Flow
globs:
alwaysApply: false
---
# Flow
A **Flow** orchestrates a graph of Nodes. You can chain Nodes in a sequence or create branching depending on the **Actions** returned from each Node's `post()`.
## 1. Action-based Transitions
Each Node's `post()` returns an **Action** string. By default, if `post()` doesn't return anything, we treat that as `"default"`.
You define transitions with the syntax:
1. **Basic default transition**: `node_a >> node_b`
This means if `node_a.post()` returns `"default"`, go to `node_b`.
(Equivalent to `node_a - "default" >> node_b`)
2. **Named action transition**: `node_a - "action_name" >> node_b`
This means if `node_a.post()` returns `"action_name"`, go to `node_b`.
It's possible to create loops, branching, or multi-step flows.
## 2. Creating a Flow
A **Flow** begins with a **start** node. You call `Flow(start=some_node)` to specify the entry point. When you call `flow.run(shared)`, it executes the start node, looks at its returned Action from `post()`, follows the transition, and continues until there's no next node.
### Example: Simple Sequence
Here's a minimal flow of two nodes in a chain:
```python
node_a >> node_b
flow = Flow(start=node_a)
flow.run(shared)
```
- When you run the flow, it executes `node_a`.
- Suppose `node_a.post()` returns `"default"`.
- The flow then sees `"default"` Action is linked to `node_b` and runs `node_b`.
- `node_b.post()` returns `"default"` but we didn't define `node_b >> something_else`. So the flow ends there.
### Example: Branching & Looping
Here's a simple expense approval flow that demonstrates branching and looping. The `ReviewExpense` node can return three possible Actions:
- `"approved"`: expense is approved, move to payment processing
- `"needs_revision"`: expense needs changes, send back for revision
- `"rejected"`: expense is denied, finish the process
We can wire them like this:
```python
# Define the flow connections
review - "approved" >> payment # If approved, process payment
review - "needs_revision" >> revise # If needs changes, go to revision
review - "rejected" >> finish # If rejected, finish the process
revise >> review # After revision, go back for another review
payment >> finish # After payment, finish the process
flow = Flow(start=review)
```
Let's see how it flows:
1. If `review.post()` returns `"approved"`, the expense moves to the `payment` node
2. If `review.post()` returns `"needs_revision"`, it goes to the `revise` node, which then loops back to `review`
3. If `review.post()` returns `"rejected"`, it moves to the `finish` node and stops
```mermaid
flowchart TD
review[Review Expense] -->|approved| payment[Process Payment]
review -->|needs_revision| revise[Revise Report]
review -->|rejected| finish[Finish Process]
revise --> review
payment --> finish
```
### Running Individual Nodes vs. Running a Flow
- `node.run(shared)`: Just runs that node alone (calls `prep->exec->post()`), returns an Action.
- `flow.run(shared)`: Executes from the start node, follows Actions to the next node, and so on until the flow can't continue.
> `node.run(shared)` **does not** proceed to the successor.
> This is mainly for debugging or testing a single node.
>
> Always use `flow.run(...)` in production to ensure the full pipeline runs correctly.
{: .warning }
## 3. Nested Flows
A **Flow** can act like a Node, which enables powerful composition patterns. This means you can:
1. Use a Flow as a Node within another Flow's transitions.
2. Combine multiple smaller Flows into a larger Flow for reuse.
3. Node `params` will be a merging of **all** parents' `params`.
### Flow's Node Methods
A **Flow** is also a **Node**, so it will run `prep()` and `post()`. However:
- It **won't** run `exec()`, as its main logic is to orchestrate its nodes.
- `post()` always receives `None` for `exec_res` and should instead get the flow execution results from the shared store.
### Basic Flow Nesting
Here's how to connect a flow to another node:
```python
# Create a sub-flow
node_a >> node_b
subflow = Flow(start=node_a)
# Connect it to another node
subflow >> node_c
# Create the parent flow
parent_flow = Flow(start=subflow)
```
When `parent_flow.run()` executes:
1. It starts `subflow`
2. `subflow` runs through its nodes (`node_a->node_b`)
3. After `subflow` completes, execution continues to `node_c`
### Example: Order Processing Pipeline
Here's a practical example that breaks down order processing into nested flows:
```python
# Payment processing sub-flow
validate_payment >> process_payment >> payment_confirmation
payment_flow = Flow(start=validate_payment)
# Inventory sub-flow
check_stock >> reserve_items >> update_inventory
inventory_flow = Flow(start=check_stock)
# Shipping sub-flow
create_label >> assign_carrier >> schedule_pickup
shipping_flow = Flow(start=create_label)
# Connect the flows into a main order pipeline
payment_flow >> inventory_flow >> shipping_flow
# Create the master flow
order_pipeline = Flow(start=payment_flow)
# Run the entire pipeline
order_pipeline.run(shared_data)
```
This creates a clean separation of concerns while maintaining a clear execution path:
```mermaid
flowchart LR
subgraph order_pipeline[Order Pipeline]
subgraph paymentFlow["Payment Flow"]
A[Validate Payment] --> B[Process Payment] --> C[Payment Confirmation]
end
subgraph inventoryFlow["Inventory Flow"]
D[Check Stock] --> E[Reserve Items] --> F[Update Inventory]
end
subgraph shippingFlow["Shipping Flow"]
G[Create Label] --> H[Assign Carrier] --> I[Schedule Pickup]
end
paymentFlow --> inventoryFlow
inventoryFlow --> shippingFlow
end
```
+101
View File
@@ -0,0 +1,101 @@
---
description: Guidelines for using PocketFlow, Core Abstraction, Node
globs:
alwaysApply: false
---
# Node
A **Node** is the smallest building block. Each Node has 3 steps `prep->exec->post`:
1. `prep(shared)`
- **Read and preprocess data** from `shared` store.
- Examples: *query DB, read files, or serialize data into a string*.
- Return `prep_res`, which is used by `exec()` and `post()`.
2. `exec(prep_res)`
- **Execute compute logic**, with optional retries and error handling (below).
- Examples: *(mostly) LLM calls, remote APIs, tool use*.
- ⚠️ This shall be only for compute and **NOT** access `shared`.
- ⚠️ If retries enabled, ensure idempotent implementation.
- Return `exec_res`, which is passed to `post()`.
3. `post(shared, prep_res, exec_res)`
- **Postprocess and write data** back to `shared`.
- Examples: *update DB, change states, log results*.
- **Decide the next action** by returning a *string* (`action = "default"` if *None*).
> **Why 3 steps?** To enforce the principle of *separation of concerns*. The data storage and data processing are operated separately.
>
> All steps are *optional*. E.g., you can only implement `prep` and `post` if you just need to process data.
{: .note }
### Fault Tolerance & Retries
You can **retry** `exec()` if it raises an exception via two parameters when define the Node:
- `max_retries` (int): Max times to run `exec()`. The default is `1` (**no** retry).
- `wait` (int): The time to wait (in **seconds**) before next retry. By default, `wait=0` (no waiting).
`wait` is helpful when you encounter rate-limits or quota errors from your LLM provider and need to back off.
```python
my_node = SummarizeFile(max_retries=3, wait=10)
```
When an exception occurs in `exec()`, the Node automatically retries until:
- It either succeeds, or
- The Node has retried `max_retries - 1` times already and fails on the last attempt.
You can get the current retry times (0-based) from `self.cur_retry`.
```python
class RetryNode(Node):
def exec(self, prep_res):
print(f"Retry {self.cur_retry} times")
raise Exception("Failed")
```
### Graceful Fallback
To **gracefully handle** the exception (after all retries) rather than raising it, override:
```python
def exec_fallback(self, prep_res, exc):
raise exc
```
By default, it just re-raises exception. But you can return a fallback result instead, which becomes the `exec_res` passed to `post()`.
### Example: Summarize file
```python
class SummarizeFile(Node):
def prep(self, shared):
return shared["data"]
def exec(self, prep_res):
if not prep_res:
return "Empty file content"
prompt = f"Summarize this text in 10 words: {prep_res}"
summary = call_llm(prompt) # might fail
return summary
def exec_fallback(self, prep_res, exc):
# Provide a simple fallback instead of crashing
return "There was an error processing your request."
def post(self, shared, prep_res, exec_res):
shared["summary"] = exec_res
# Return "default" by not returning
summarize_node = SummarizeFile(max_retries=3)
# node.run() calls prep->exec->post
# If exec() fails, it retries up to 3 times before calling exec_fallback()
action_result = summarize_node.run(shared)
print("Action returned:", action_result) # "default"
print("Summary stored:", shared["summary"])
```
@@ -0,0 +1,54 @@
---
description: Guidelines for using PocketFlow, Core Abstraction, (Advanced) Parallel
globs:
alwaysApply: false
---
# (Advanced) Parallel
**Parallel** Nodes and Flows let you run multiple **Async** Nodes and Flows **concurrently**—for example, summarizing multiple texts at once. This can improve performance by overlapping I/O and compute.
> Because of Pythons GIL, parallel nodes and flows cant truly parallelize CPU-bound tasks (e.g., heavy numerical computations). However, they excel at overlapping I/O-bound work—like LLM calls, database queries, API requests, or file I/O.
{: .warning }
> - **Ensure Tasks Are Independent**: If each item depends on the output of a previous item, **do not** parallelize.
>
> - **Beware of Rate Limits**: Parallel calls can **quickly** trigger rate limits on LLM services. You may need a **throttling** mechanism (e.g., semaphores or sleep intervals).
>
> - **Consider Single-Node Batch APIs**: Some LLMs offer a **batch inference** API where you can send multiple prompts in a single call. This is more complex to implement but can be more efficient than launching many parallel requests and mitigates rate limits.
{: .best-practice }
## AsyncParallelBatchNode
Like **AsyncBatchNode**, but run `exec_async()` in **parallel**:
```python
class ParallelSummaries(AsyncParallelBatchNode):
async def prep_async(self, shared):
# e.g., multiple texts
return shared["texts"]
async def exec_async(self, text):
prompt = f"Summarize: {text}"
return await call_llm_async(prompt)
async def post_async(self, shared, prep_res, exec_res_list):
shared["summary"] = "\n\n".join(exec_res_list)
return "default"
node = ParallelSummaries()
flow = AsyncFlow(start=node)
```
## AsyncParallelBatchFlow
Parallel version of **BatchFlow**. Each iteration of the sub-flow runs **concurrently** using different parameters:
```python
class SummarizeMultipleFiles(AsyncParallelBatchFlow):
async def prep_async(self, shared):
return [{"filename": f} for f in shared["files"]]
sub_flow = AsyncFlow(start=LoadAndSummarizeFile())
parallel_flow = SummarizeMultipleFiles(start=sub_flow)
await parallel_flow.run_async(shared)
```