# Session Report

**Session ID:** 3f710018-6d5e-4387-a693-aaa9ace80bba

---

## 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 OpenAPI specification types and JSON parsers

## Overview
Create the data types and JSON parsers needed to parse OpenAPI 3.x specifications.

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

### Data Types
```haskell
-- Top-level OpenAPI spec
data OpenAPISpec = OpenAPISpec
    { specPaths :: Map Path (Map Method Operation)
    , specComponents :: Maybe Components
    }

-- Path and method types
type Path = Text
type Method = Text -- GET, POST, etc.

-- Operation (an endpoint)
data Operation = Operation
    { opOperationId :: Maybe Text
    , opSummary :: Maybe Text
    , opDescription :: Maybe Text
    , opParameters :: [Parameter]
    , opRequestBody :: Maybe RequestBody
    }

-- Parameter (path, query, header)
data Parameter = Parameter
    { paramName :: Text
    , paramIn :: ParamLocation  -- Path | Query | Header
    , paramDescription :: Maybe Text
    , paramRequired :: Bool
    , paramSchema :: Maybe Schema
    }

data ParamLocation = ParamInPath | ParamInQuery | ParamInHeader

-- Request body
data RequestBody = RequestBody
    { reqBodyDescription :: Maybe Text
    , reqBodyRequired :: Bool
    , reqBodyContent :: Map MediaType Schema  -- key: "application/json"
    }

type MediaType = Text

-- JSON Schema (subset needed for OpenAPI)
data Schema = Schema
    { schemaType :: Maybe Text          -- "string", "integer", "array", "object"
    , schemaDescription :: Maybe Text
    , schemaEnum :: Maybe [Aeson.Value] -- For enum values
    , schemaProperties :: Maybe (Map Text Schema)
    , schemaItems :: Maybe Schema       -- For arrays
    , schemaAnyOf :: Maybe [Schema]     -- For anyOf unions
    , schemaRef :: Maybe Text           -- $ref like "#/components/schemas/Foo"
    , schemaRequired :: Maybe [Text]
    }

-- Components section for reusable schemas
data Components = Components
    { componentsSchemas :: Maybe (Map Text Schema)
    }
```

### JSON Instances
- Implement `FromJSON` for all types
- Handle optional fields correctly
- Parse `$ref` fields properly

### Notes
- Focus on the subset of OpenAPI 3.0/3.1 used by most APIs
- Don't need to implement full OpenAPI spec - just what's needed for tool generation
- Use existing aeson patterns from the codebase (e.g., `(.:?)` for optional fields)

## Acceptance Criteria
- [ ] All types defined with proper JSON parsing
- [ ] Can parse a sample OpenAPI spec (e.g., Petstore)
- [ ] Unit tests for parsing

## Related Files to Reference
- `src/System/Agents/MCP/Base.hs` - similar pattern for JSON types
- `src/System/Agents/ToolSchema.hs` - existing schema types

## Tradeoffs
- **Scope**: Only implement the OpenAPI subset needed for LLM tool generation (not full spec compliance)
- **Reference Resolution**: `$ref` resolution will be handled in a separate issue to keep this one focused




---
Please mention issue #95 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 see what patterns are being used for JSON types.
</details>

### Response



### Tool Calls

- **bash_list-files**

---

## Step 3: User Turn



---

## Step 4: LLM Turn

### Thinking Process

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

Let me look at the referenced files to understand the patterns used in this codebase:
1. `src/System/Agents/MCP/Base.hs` - similar pattern for JSON types
2. `src/System/Agents/ToolSchema.hs` - existing schema types

Let me also check if there's an OpenAPI directory structure already.
</details>

### Response



### Tool Calls

- **bash_read-file**
- **bash_read-file**

---

## Step 5: User Turn



---

## Step 6: LLM Turn

### Thinking Process

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

Now I understand the codebase patterns. Let me look at the cabal file to understand dependencies and see if there are any existing OpenAPI references.
</details>

### Response



### Tool Calls

- **bash_read-file**

---

## Step 7: User Turn



---

## Step 8: LLM Turn

### Thinking Process

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

Now let me also check the test file to understand how tests are structured in this project.
</details>

### Response



### Tool Calls

- **bash_read-file**

---

## Step 9: User Turn



---

## Step 10: LLM Turn

### Thinking Process

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

Now I have a good understanding of the codebase patterns. Let me create the OpenAPI Types module. Based on the patterns I've seen:

1. They use `OverloadedStrings` and `OverloadedRecordDot` extensions
2. They use `Data.Aeson` with `FromJSON` and `ToJSON` instances
3. They use `(.:?)` for optional fields and `(.:)` for required fields
4. They use `withObject` for parsing objects
5. They have custom helper operators like `.=?` and `.=` for building JSON objects
6. They use `Text` for strings

Now I need to create the OpenAPI types module. I'll also need to add tests for the parsing functionality.

Let me create the module at `src/System/Agents/Tools/OpenAPI/Types.hs`.
</details>

### Response

Now I have a good understanding of the codebase. Let me create the OpenAPI types module following the existing patterns.

### Tool Calls

- **bash_write-file**

---

## Step 11: User Turn



---

## Step 12: LLM Turn

### Thinking Process

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

Now I need to add the module to the cabal file and add tests. Let me update the cabal file first.
</details>

### Response

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

### Tool Calls

- **bash_read-file**

---

## Step 13: User Turn



---

## Step 14: LLM Turn

### Thinking Process

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

I need to add the new module `System.Agents.Tools.OpenAPI.Types` to the exposed-modules list. Let me update the cabal file.
</details>

### Response



### Tool Calls

- **bash_write-file**

---

## Step 15: User Turn



---

## Step 16: LLM Turn

### Thinking Process

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

Now let me check if the code compiles:
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 17: User Turn



---

## Step 18: LLM Turn

### Thinking Process

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

I have several compilation errors. I need to fix the imports and use the correct functions from the `Data.Aeson` module. Let me fix the module:1. `Aeson.Parser` - I should import `Data.Aeson.Types (Parser)` instead
2. `Aeson.toText` - This doesn't exist. I need to use `Data.Aeson.Key` to convert between Key and Text
3. `Aeson.fromText` - Similarly doesn't exist

Let me look at what the MCP/Base.hs module does for reference on how they handle these types of conversions. Looking at the MCP/Base.hs, I see that they use `Aeson.Key` module functions. Let me check the imports there.

Looking at MCP/Base.hs:- They import `Data.Aeson` and `Data.Aeson.KeyMap`
- They use `.:` and `.:?` from `Data.Aeson`
- For keys, they seem to use `Aeson.fromText` which must come from somewhere else

Let me check what aeson version they're using and what the proper imports are. It looks like they use `Data.Aeson.Key` for key conversions.

Let me update the file with the correct imports.
</details>

### Response

I need to fix the imports. Let me update the module with proper imports from `Data.Aeson.Key` and `Data.Aeson.Types`:

### Tool Calls

- **bash_write-file**

---

## Step 19: User Turn



---

## Step 20: LLM Turn

### Thinking Process

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

Now let's try compiling again.
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 21: User Turn



---

## Step 22: LLM Turn

### Thinking Process

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

I need to import `Data.Aeson.KeyMap` (which exports `Pair`) properly. Let me check what the correct module path is for `Pair`. Looking at the aeson library, `Pair` is exported from `Data.Aeson` (in aeson 2.0+) or from `Data.Aeson.KeyMap`. Let me look at how the MCP/Base module handles this.

In MCP/Base.hs, they import:
```haskell
import qualified Data.Aeson as Aeson
import qualified Data.Aeson.KeyMap as Aeson
```

And they use `Aeson.Pair`. This means `Pair` comes from `Data.Aeson.KeyMap`. But the error says it's not exported. Let me check the aeson documentation - it might be that in the version used here (>=2.2.0.0), `Pair` is defined elsewhere.

Actually, looking at the aeson 2.x documentation, `Pair` is exported from `Data.Aeson.KeyMap`. But the import is already there. Let me try a different approach - maybe I need to import `Data.Aeson.KeyMap` differently.

Wait, I see the issue - I have `import qualified Data.Aeson.KeyMap as Aeson` which shadows things. Let me check how the MCP/Base module does it...

Actually looking at the error messages more carefully, it seems like the qualified import of `Data.Aeson.KeyMap as Aeson` might not be exposing `Pair`. Let me try importing `Pair` explicitly or using a different approach.

Looking at the aeson 2.0+ API:
- `Data.Aeson.KeyMap` exports `Pair` (type alias for `(Key, Value)`)

Let me fix this by importing Pair from the right place.
</details>

### Response



### Tool Calls

- **bash_write-file**

---

## Step 23: User Turn



---

## Step 24: LLM Turn

### Thinking Process

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

Let me compile again to see if it works now.
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 25: User Turn



---

## Step 26: LLM Turn

### Thinking Process

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

I see, `Pair` is not exported from `Data.Aeson.KeyMap` in this version. Looking at the MCP/Base module, I see that they use `Aeson.Pair` which is a type alias for `(Key, Value)`. Let me check where it comes from in that module...

Actually, let me check the aeson 2.x documentation again. In aeson 2.0+, `Pair` is exported from `Data.Aeson.KeyMap` as a type synonym. But since this isn't working, maybe it's from a different place or has a different name.

Let me look at the version of aeson used. According to cabal file, it's `aeson >=2.2.0.0`. In newer versions of aeson, `Pair` might be defined differently.

Let me try using the type directly: `(Key, Value)` or check what `Aeson.Pair` resolves to in MCP/Base.hs.

Actually, let me just look at how MCP/Base.hs does it - they have `import qualified Data.Aeson.KeyMap as Aeson` and then use `Aeson.Pair`. But in my case I have `import qualified Data.Aeson.KeyMap as KeyMap` so I should use `KeyMap.Pair`. Let me check if that's exported...

Actually, looking at the aeson 2.2 documentation, `Pair` is exported from `Data.Aeson` as a type synonym for `(Key, Value)`. Let me try importing it from there.
</details>

### Response



### Tool Calls

- **bash_write-file**

---

## Step 27: User Turn



---

## Step 28: LLM Turn

### Thinking Process

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

Let me try to compile again.
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 29: User Turn



---

## Step 30: LLM Turn

### Thinking Process

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

I see the issue - my `.=` and `.=?` operators return `Maybe Pair`, but `Aeson.object` expects `[Pair]`. I need to filter out the Nothings like they do in MCP/Base.hs. Let me look at that approach more carefully:

In MCP/Base.hs:
```haskell
object :: [Maybe Aeson.Pair] -> Aeson.Value
object = Aeson.object . Maybe.catMaybes
```

And they use it like:
```haskell
instance ToJSON Foo where
    toJSON x = object ["field" .= x.field, "opt" .=? x.optField]
```

So they have a custom `object` function that handles `Maybe Pair`! Let me update my code to use the same pattern.
</details>

### Response

I see - I need a custom `object` function that filters out the Nothings, like in MCP/Base.hs. Let me update the code:

### Tool Calls

- **bash_write-file**

---

## Step 31: User Turn



---

## Step 32: LLM Turn

### Thinking Process

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

Let me try compiling again.
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 33: User Turn



---

## Step 34: LLM Turn

### Thinking Process

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

The code compiles successfully. Now I need to add tests for the OpenAPI types. Let me update the test file to include tests for parsing OpenAPI specifications.
</details>

### Response

The code compiles successfully. Now let me add unit tests for the OpenAPI types:

### Tool Calls

- **bash_read-file**

---

## Step 35: User Turn



---

## Step 36: LLM Turn

### Thinking Process

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

Now I need to add OpenAPI tests. Let me add a new test module to the test file.
</details>

### Response



### Tool Calls

- **bash_write-file**

---

## Step 37: User Turn



---

## Step 38: LLM Turn

### Thinking Process

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

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

### Response



### Tool Calls

- **bash_check-code**

---

## Step 39: User Turn



---

## Step 40: LLM Turn

### Thinking Process

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

All 56 tests pass, including the 10 new OpenAPI tests. Let me also clean up the unused import warning by removing `withText` from the imports.
</details>

### Response

All tests pass. Let me clean up the unused import warning:

### Tool Calls

- **bash_write-file**

---

## Step 41: User Turn



---

## Step 42: LLM Turn

### Thinking Process

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

Let me run the tests again to make sure everything still compiles and works.
</details>

### Response



### Tool Calls

- **bash_check-code**

---

## Step 43: User Turn



---

## Step 44: LLM Turn

### Thinking Process

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

All 56 tests pass. The module is complete with no warnings. Let me summarize what was implemented:

1. Created `src/System/Agents/Tools/OpenAPI/Types.hs` with:
   - `OpenAPISpec` - top-level OpenAPI spec with paths and components
   - `Operation` - represents an API endpoint with operationId, summary, description, parameters, requestBody
   - `Parameter` - represents path, query, or header parameters with name, location, description, required flag, and schema
   - `ParamLocation` - enum for path/query/header parameter locations
   - `RequestBody` - represents request body with description, required flag, and content map
   - `Schema` - JSON schema subset with type, description, enum, properties, items, anyOf, ref, and required fields
   - `Components` - reusable schema definitions

2. Implemented `FromJSON` and `ToJSON` instances for all types

3. Added the module to `agents.cabal`

4. Added 10 comprehensive unit tests for:
   - Minimal OpenAPI spec parsing
   - Path and method parsing
   - Parameter parsing (path, query)
   - Schema parsing ($ref, inline with properties)
   - Request body parsing
   - Components parsing
   - Round-trip serialization

The implementation follows the existing codebase patterns from `System.Agents.MCP.Base` and uses modern Haskell practices.
</details>

### Response

All tests pass. Let me provide a summary of the implementation:

Implement OpenAPI specification types and JSON parsers (#95)

This commit adds the data types and JSON parsers needed to parse OpenAPI 3.x specifications for LLM tool generation.

Changes:
- Created `src/System/Agents/Tools/OpenAPI/Types.hs` with complete OpenAPI types:
  - `OpenAPISpec` - Top-level specification with paths and components
  - `Operation` - API endpoint representation (operationId, summary, description, etc.)
  - `Parameter` - Path/query/header parameters with location, required flag, and schema
  - `ParamLocation` - Enum for parameter locations (path/query/header)
  - `RequestBody` - Request body with content type to schema mapping
  - `Schema` - JSON Schema subset supporting type, properties, items, anyOf, $ref, etc.
  - `Components` - Reusable schema definitions

- Implemented `FromJSON` and `ToJSON` instances for all types following existing
  codebase patterns from `System.Agents.MCP.Base`

- Added the module to `agents.cabal` exposed modules

- Added 10 comprehensive unit tests covering:
  - Minimal spec parsing
  - Path and method parsing
  - Parameter parsing (path, query locations)
  - Schema parsing ($ref references and inline with properties)
  - Request body parsing
  - Components section parsing
  - Round-trip JSON serialization

The implementation focuses on the OpenAPI subset needed for tool generation
rather than full spec compliance. Reference resolution ($ref) will be handled
in a separate issue as noted in the tradeoffs.

Closes #95
