# Session Report

**Session ID:** ea0e7142-3ad2-4ca1-b7df-7b77a531eb0a

---

## Step 1: User Turn

### System Prompt

```
You are an expert Haskell and Bash programmer specialized in writing clean, idiomatic, and efficient Haskell code.
When writing Bash code:
- Avoid bash-specific logic but bash-ism are fine.
- Document required shell tools at the top of the bash script.
When writing Haskell code:
- Use modern Haskell practices (base >= 4.14)
- Prefer pure functions and explicit type signatures
- Use standard libraries when appropriate
- Add clear comments for complex logic
- Follow consistent formatting
Use list-files to explore the project structure, read-file to understand existing code, write-file to create or modify files, and check-code to verify your work.
Always compile code before considering the job done.
Your last message will serve as git-commit. Format your final message as follows:
- Start with a one-liner commit message in imperative mode (e.g., 'Fix bug in user authentication')
- The one-liner should reference the fixed issue (e.g., 'Fix bug in user authentication (#12345)')
- Follow with a blank line, then a body with a nice summary of the changes
- In the body, reference the fixed issue using 'Closes #12345' format

Example format:
Fix critical bug in session handling (#75)

This commit resolves the memory leak caused by not properly
closing session handles. The fix ensures all resources are
released when a session is terminated.

Closes #75
```

### User Query

# Implement JSON Schema reference resolution ($ref dereferencing)

## Overview
Implement recursive `$ref` resolution for OpenAPI schemas. This is essential because OpenAPI specs use references to avoid duplication.

## Scope
Create a new module `src/System/Agents/Tools/OpenAPI/Resolver.hs`:

### Core Function
```haskell
-- | Recursively resolves $ref pointers in a schema
resolveSchema :: 
    Schema -> 
    Components -> 
    Schema

-- | Resolves all schemas within an OpenAPI spec
dereferenceSpec :: OpenAPISpec -> OpenAPISpec
```

### Algorithm
The Python implementation:
```python
def resolve_schema(schema, components):
    if not schema:
        return {}
    if "$ref" in schema:
        ref_path = schema["$ref"]
        ref_parts = ref_path.strip("#/").split("/")
        resolved = components
        for part in ref_parts[1:]:  # Skip 'components'
            resolved = resolved.get(part, {})
        return resolve_schema(resolved, components)
    
    # Recursively resolve nested schemas
    if "properties" in schema:
        for prop, prop_schema in schema["properties"].items():
            resolved_schema["properties"][prop] = resolve_schema(prop_schema, components)
    
    if "items" in schema:
        resolved_schema["items"] = resolve_schema(resolved_schema["items"], components)
    
    return resolved_schema
```

### Implementation Details
- Parse `$ref` paths like `#/components/schemas/Pet`
- Walk through components to find referenced schemas
- Recursively resolve until no more `$ref`s remain
- Handle circular references gracefully (detect and error, or limit depth)
- Deep copy/clone schemas to avoid mutation issues

### Helper Types
```haskell
-- Represents a parsed reference path
data RefPath = RefPath 
    { refComponents :: Text  -- "components"
    , refSection :: Text     -- "schemas"
    , refName :: Text        -- "Pet"
    }

parseRef :: Text -> Maybe RefPath
```

## Acceptance Criteria
- [ ] Can resolve simple `$ref` like `#/components/schemas/Pet`
- [ ] Recursively resolves nested references (schema A refs B refs C)
- [ ] Handles arrays with item references
- [ ] Handles object properties with references
- [ ] Returns meaningful errors for unresolvable references
- [ ] Unit tests for various reference patterns

## Edge Cases to Handle
1. **Circular references**: Schema A references Schema B which references Schema A
2. **Missing references**: `$ref` points to non-existent schema
3. **Nested paths**: `#/components/schemas/Nested/Deep` (less common)
4. **External refs**: `http://example.com/schema.json` (out of scope - can error)

## Related Files
- `src/System/Agents/Tools/OpenAPI/Types.hs` - depends on types from issue #98




---
Please mention issue #96 in the commit message.



### Available Tools

- **bash_grep-files** (`bash_grep-files`)
  - Description: Search for a pattern in files using 'git grep'
- **bash_check-code** (`bash_check-code`)
  - Description: Check Haskell code by compiling or testing
- **bash_write-file** (`bash_write-file`)
  - Description: Write content to a file
- **bash_list-files** (`bash_list-files`)
  - Description: List all files in the project
- **bash_read-file** (`bash_read-file`)
  - Description: Read the contents of a file

---

## Step 2: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Let me start by exploring the project structure to understand the codebase and find the relevant files.
</details>

### Response



### Tool Calls

- **bash_list-files**

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## Step 3: User Turn



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## Step 4: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Let me look at the OpenAPI Types module to understand the existing types that I need to work with.
</details>

### Response



### Tool Calls

- **bash_read-file**

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## Step 5: User Turn



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## Step 6: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now I have a clear picture of the types. Let me also look at the cabal file to understand the project dependencies and structure.
</details>

### Response



### Tool Calls

- **bash_read-file**

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## Step 7: User Turn



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## Step 8: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now I have a good understanding of the existing types. Let me also look at the test file to understand the testing pattern used.
</details>

### Response



### Tool Calls

- **bash_read-file**

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## Step 9: User Turn



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## Step 10: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now I have a good understanding of the codebase. Let me create the Resolver module that implements JSON Schema reference resolution. I'll need to:

1. Create `src/System/Agents/Tools/OpenAPI/Resolver.hs`
2. Update the cabal file to include the new module
3. Add unit tests for the resolver

Let me implement the Resolver module first.
</details>

### Response

Now I have a clear picture of the types and the testing patterns. Let me implement the Resolver module.

### Tool Calls

- **bash_write-file**

---

## Step 11: User Turn



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## Step 12: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me update the cabal file to include the new module.
</details>

### Response

Now let me update the cabal file to include the new module:

### Tool Calls

- **bash_write-file**

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## Step 13: User Turn



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## Step 14: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me compile the code to ensure it works correctly before writing the tests.
</details>

### Response

Let me compile the code first to make sure it works:

### Tool Calls

- **bash_check-code**

---

## Step 15: User Turn



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## Step 16: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

The code compiles successfully. I just need to fix the unused import warning. Let me also add comprehensive tests for the resolver module. First, let me fix the import issue.
</details>

### Response

The code compiles. Let me fix the warning and add comprehensive tests:

### Tool Calls

- **bash_write-file**

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## Step 17: User Turn



---

## Step 18: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me add comprehensive unit tests for the resolver module.
</details>

### Response

Now let me add comprehensive tests for the resolver:

### Tool Calls

- **bash_write-file**

---

## Step 19: User Turn



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## Step 20: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me compile and run the tests to make sure everything works.
</details>

### Response

Now let me run the tests to make sure everything works:

### Tool Calls

- **bash_check-code**

---

## Step 21: User Turn



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## Step 22: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

I need to fix the test file - there are some variable ordering issues. Let me correct the tests.
</details>

### Response

I need to fix the test file. The variable declarations need to be ordered correctly:

### Tool Calls

- **bash_write-file**

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## Step 23: User Turn



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## Step 24: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me run the tests again to make sure everything compiles and runs correctly.
</details>

### Response



### Tool Calls

- **bash_check-code**

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## Step 25: User Turn



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## Step 26: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

I see the issue - in the OpenAPI types, the schemaProperties is `Maybe (Map Text Schema)` but it's at the wrong position in the Schema constructor. Let me check the Schema type definition again.
</details>

### Response

Let me check the Schema type definition to understand the constructor order:

### Tool Calls

- **bash_grep-files**

---

## Step 27: User Turn



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## Step 28: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Let me look at the Schema type definition again:
</details>

### Response



### Tool Calls

- **bash_read-file**

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## Step 29: User Turn



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## Step 30: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Looking at the Schema type:

```haskell
data Schema = Schema
    { schemaType :: Maybe Text
    , schemaDescription :: Maybe Text
    , schemaEnum :: Maybe [Aeson.Value]       -- position 3
    , schemaProperties :: Maybe (Map Text Schema)  -- position 4
    , schemaItems :: Maybe Schema             -- position 5
    , schemaAnyOf :: Maybe [Schema]           -- position 6
    , schemaRef :: Maybe Text                 -- position 7
    , schemaRequired :: Maybe [Text]          -- position 8
    }
```

So the order is:
1. schemaType
2. schemaDescription
3. schemaEnum
4. schemaProperties
5. schemaItems
6. schemaAnyOf
7. schemaRef
8. schemaRequired

In my tests I'm using the wrong field order. Let me fix them.
</details>

### Response

I see the issue - I had the field order wrong in the tests. The Schema constructor is:
1. schemaType
2. schemaDescription
3. schemaEnum
4. schemaProperties
5. schemaItems
6. schemaAnyOf
7. schemaRef
8. schemaRequired

Let me fix the tests:

### Tool Calls

- **bash_write-file**

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## Step 31: User Turn



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## Step 32: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me run the tests again to verify they compile and pass.
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 33: User Turn



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## Step 34: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

I need to fix the type signature in the tests - should be `Map.Map` instead of just `Map`.
</details>

### Response



### Tool Calls

- **bash_write-file**

---

## Step 35: User Turn



---

## Step 36: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Now let me run the tests again.
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 37: User Turn



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## Step 38: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

All 72 tests pass. Let me now do a final compile check to make sure everything is clean.
</details>

### Response

All tests pass. Let me do a final compile to ensure everything is clean:

### Tool Calls

- **bash_check-code**

---

## Step 39: User Turn



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## Step 40: LLM Turn

### Thinking Process

<details>
<summary>Click to expand reasoning</summary>

Everything compiles cleanly with no errors. Let me provide a summary of the work done.
</details>

### Response

Everything compiles cleanly. Here's a summary of what was implemented:

Implement JSON Schema reference resolution ($ref dereferencing) (#96)

This commit implements recursive `$ref` resolution for OpenAPI schemas,
essential for handling OpenAPI specifications that use references to avoid
duplication.

Changes include:

**New module: `src/System/Agents/Tools/OpenAPI/Resolver.hs`**

Core functions:
- `resolveSchema` - Recursively resolves all `$ref` pointers in a schema
- `dereferenceSpec` - Resolves all schemas within an OpenAPI spec
- `parseRef` - Parses reference paths like `#/components/schemas/Pet`
- `resolveRef` - Looks up referenced schemas from components

**Key features:**
- Supports simple references (`#/components/schemas/Pet`)
- Handles nested references (schema A refs B refs C)
- Handles arrays with item references
- Handles object properties with references
- Handles anyOf schemas with references
- Detects circular references with proper error handling
- Returns meaningful errors for unresolvable references
- Maximum recursion depth limit (100) to prevent infinite loops
- External refs (http/https) return `Nothing` from parseRef

**Helper types:**
- `RefPath` - Represents a parsed reference path
- `ResolutionError` - Errors that can occur during resolution
  - `InvalidRefPath` - Malformed or unsupported reference
  - `SchemaNotFound` - Referenced schema not in components
  - `CircularReference` - Circular reference detected
  - `MaxDepthExceeded` - Recursion limit reached

**Unit tests added:**
- Reference path parsing (valid refs, external refs, nested paths)
- Simple $ref resolution
- Nested reference resolution
- Array item references
- anyOf references
- Circular reference detection
- Missing reference handling
- Full spec dereferencing

Closes #96
