Introduce "agents"

An agent is currently a name given to a system prompt and a set of
tools which the agent has access to.

This resolves the previous issue of the set of configured tools being
available in *all* contexts, which wasn't always desired. Tools are now
only available when an agent is explicitly requested using the
`-a/--agent` flag.

Agents are expected to be expanded on: the concept of task-specilized
agents (e.g. coding), the ability to define a set of files an agent
should always have access to for RAG purposes, etc.

Other changes:

- Removes the "tools" top-level config structure (though this is expected
to come back along with the abillity to define custom tools).

- Renamed `pkg/agent` to `pkg/agents`

pkg/agents/toolbox/dir_tree.go

@@ -0,0 +1,142 @@
+package toolbox
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	toolutil "git.mlow.ca/mlow/lmcli/pkg/agents/toolbox/util"
+	"git.mlow.ca/mlow/lmcli/pkg/api"
+)
+
+const TREE_DESCRIPTION = `Retrieve a tree-like view of a directory's contents.
+
+Use these results for your own reference in completing your task, they do not need to be shown to the user.
+
+Example result:
+{
+	"message": "success",
+	"result": ".
+├── a_directory/
+│   ├── file1.txt (100 bytes)
+│   └── file2.txt (200 bytes)
+├── a_file.txt (123 bytes)
+└── another_file.txt (456 bytes)"
+}
+`
+
+var DirTreeTool = api.ToolSpec{
+	Name:        "dir_tree",
+	Description: TREE_DESCRIPTION,
+	Parameters: []api.ToolParameter{
+		{
+			Name:        "relative_path",
+			Type:        "string",
+			Description: "If set, display the tree starting from this path relative to the current one.",
+		},
+		{
+			Name:        "depth",
+			Type:        "integer",
+			Description: "Depth of directory recursion. Defaults to 0 (no recursion), maximum of 5.",
+		},
+	},
+	Impl: func(tool *api.ToolSpec, args map[string]interface{}) (string, error) {
+		var relativeDir string
+		if tmp, ok := args["relative_path"]; ok {
+			relativeDir, ok = tmp.(string)
+			if !ok {
+				return "", fmt.Errorf("expected string for relative_path, got %T", tmp)
+			}
+		}
+
+		var depth int = 0 // Default value if not provided
+		if tmp, ok := args["depth"]; ok {
+			switch v := tmp.(type) {
+			case float64:
+				depth = int(v)
+			case string:
+				var err error
+				if depth, err = strconv.Atoi(v); err != nil {
+					return "", fmt.Errorf("invalid `depth` value, expected integer but got string that cannot convert: %v", tmp)
+				}
+				depth = max(0, min(5, depth))
+			default:
+				return "", fmt.Errorf("expected int or string for max_depth, got %T", tmp)
+			}
+		}
+
+		result := tree(relativeDir, depth)
+		ret, err := result.ToJson()
+		if err != nil {
+			return "", fmt.Errorf("could not serialize result: %v", err)
+		}
+		return ret, nil
+	},
+}
+
+func tree(path string, depth int) api.CallResult {
+	if path == "" {
+		path = "."
+	}
+	ok, reason := toolutil.IsPathWithinCWD(path)
+	if !ok {
+		return api.CallResult{Message: reason}
+	}
+
+	var treeOutput strings.Builder
+	treeOutput.WriteString(path + "\n")
+	err := buildTree(&treeOutput, path, "", depth)
+	if err != nil {
+		return api.CallResult{
+			Message: err.Error(),
+		}
+	}
+
+	return api.CallResult{Result: treeOutput.String()}
+}
+
+func buildTree(output *strings.Builder, path string, prefix string, depth int) error {
+	files, err := os.ReadDir(path)
+	if err != nil {
+		return err
+	}
+
+	for i, file := range files {
+		if strings.HasPrefix(file.Name(), ".") {
+			// Skip hidden files and directories
+			continue
+		}
+
+		isLast := i == len(files)-1
+		var branch string
+		if isLast {
+			branch = "└── "
+		} else {
+			branch = "├── "
+		}
+
+		info, _ := file.Info()
+		size := info.Size()
+		sizeStr := fmt.Sprintf(" (%d bytes)", size)
+
+		output.WriteString(prefix + branch + file.Name())
+		if file.IsDir() {
+			output.WriteString("/\n")
+			if depth > 0 {
+				var nextPrefix string
+				if isLast {
+					nextPrefix = prefix + "    "
+				} else {
+					nextPrefix = prefix + "│   "
+				}
+				buildTree(output, filepath.Join(path, file.Name()), nextPrefix, depth-1)
+			}
+		} else {
+			output.WriteString(sizeStr + "\n")
+		}
+	}
+
+	return nil
+}

pkg/agents/toolbox/file_insert_lines.go

@@ -0,0 +1,114 @@
+package toolbox
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	toolutil "git.mlow.ca/mlow/lmcli/pkg/agents/toolbox/util"
+	"git.mlow.ca/mlow/lmcli/pkg/api"
+)
+
+const FILE_INSERT_LINES_DESCRIPTION = `Insert lines into a file, must specify path.
+
+Make sure your inserts match the flow and indentation of surrounding content.`
+
+var FileInsertLinesTool = api.ToolSpec{
+	Name:        "file_insert_lines",
+	Description: FILE_INSERT_LINES_DESCRIPTION,
+	Parameters: []api.ToolParameter{
+		{
+			Name:        "path",
+			Type:        "string",
+			Description: "Path of the file to be modified, relative to the current working directory.",
+			Required:    true,
+		},
+		{
+			Name:        "position",
+			Type:        "integer",
+			Description: `Which line to insert content *before*.`,
+			Required:    true,
+		},
+		{
+			Name:        "content",
+			Type:        "string",
+			Description: `The content to insert.`,
+			Required:    true,
+		},
+	},
+	Impl: func(tool *api.ToolSpec, args map[string]interface{}) (string, error) {
+		tmp, ok := args["path"]
+		if !ok {
+			return "", fmt.Errorf("path parameter to write_file was not included.")
+		}
+		path, ok := tmp.(string)
+		if !ok {
+			return "", fmt.Errorf("Invalid path in function arguments: %v", tmp)
+		}
+		var position int
+		tmp, ok = args["position"]
+		if ok {
+			tmp, ok := tmp.(float64)
+			if !ok {
+				return "", fmt.Errorf("Invalid position in function arguments: %v", tmp)
+			}
+			position = int(tmp)
+		}
+		var content string
+		tmp, ok = args["content"]
+		if ok {
+			content, ok = tmp.(string)
+			if !ok {
+				return "", fmt.Errorf("Invalid content in function arguments: %v", tmp)
+			}
+		}
+
+		result := fileInsertLines(path, position, content)
+		ret, err := result.ToJson()
+		if err != nil {
+			return "", fmt.Errorf("Could not serialize result: %v", err)
+		}
+		return ret, nil
+	},
+}
+
+func fileInsertLines(path string, position int, content string) api.CallResult {
+	ok, reason := toolutil.IsPathWithinCWD(path)
+	if !ok {
+		return api.CallResult{Message: reason}
+	}
+
+	// Read the existing file's content
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if !os.IsNotExist(err) {
+			return api.CallResult{Message: fmt.Sprintf("Could not read path: %s", err.Error())}
+		}
+		_, err = os.Create(path)
+		if err != nil {
+			return api.CallResult{Message: fmt.Sprintf("Could not create new file: %s", err.Error())}
+		}
+		data = []byte{}
+	}
+
+	if position < 1 {
+		return api.CallResult{Message: "start_line cannot be less than 1"}
+	}
+
+	lines := strings.Split(string(data), "\n")
+	contentLines := strings.Split(strings.Trim(content, "\n"), "\n")
+
+	before := lines[:position-1]
+	after := lines[position-1:]
+	lines = append(before, append(contentLines, after...)...)
+
+	newContent := strings.Join(lines, "\n")
+
+	// Join the lines and write back to the file
+	err = os.WriteFile(path, []byte(newContent), 0644)
+	if err != nil {
+		return api.CallResult{Message: fmt.Sprintf("Could not write to path: %s", err.Error())}
+	}
+
+	return api.CallResult{Result: newContent}
+}

pkg/agents/toolbox/file_replace_lines.go

@@ -0,0 +1,133 @@
+package toolbox
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	toolutil "git.mlow.ca/mlow/lmcli/pkg/agents/toolbox/util"
+	"git.mlow.ca/mlow/lmcli/pkg/api"
+)
+
+const FILE_REPLACE_LINES_DESCRIPTION = `Replace or remove a range of lines within a file, must specify path.
+
+Useful for re-writing snippets/blocks of code or entire functions.
+
+Plan your edits carefully and ensure any new content matches the flow and indentation of surrounding text.`
+
+var FileReplaceLinesTool = api.ToolSpec{
+	Name:        "file_replace_lines",
+	Description: FILE_REPLACE_LINES_DESCRIPTION,
+	Parameters: []api.ToolParameter{
+		{
+			Name:        "path",
+			Type:        "string",
+			Description: "Path of the file to be modified, relative to the current working directory.",
+			Required:    true,
+		},
+		{
+			Name:        "start_line",
+			Type:        "integer",
+			Description: `Line number which specifies the start of the replacement range (inclusive).`,
+			Required:    true,
+		},
+		{
+			Name:        "end_line",
+			Type:        "integer",
+			Description: `Line number which specifies the end of the replacement range (inclusive). If unset, range extends to end of file.`,
+		},
+		{
+			Name:        "content",
+			Type:        "string",
+			Description: `Content to replace specified range. Omit to remove the specified range.`,
+		},
+	},
+	Impl: func(tool *api.ToolSpec, args map[string]interface{}) (string, error) {
+		tmp, ok := args["path"]
+		if !ok {
+			return "", fmt.Errorf("path parameter to write_file was not included.")
+		}
+		path, ok := tmp.(string)
+		if !ok {
+			return "", fmt.Errorf("Invalid path in function arguments: %v", tmp)
+		}
+		var start_line int
+		tmp, ok = args["start_line"]
+		if ok {
+			tmp, ok := tmp.(float64)
+			if !ok {
+				return "", fmt.Errorf("Invalid start_line in function arguments: %v", tmp)
+			}
+			start_line = int(tmp)
+		}
+		var end_line int
+		tmp, ok = args["end_line"]
+		if ok {
+			tmp, ok := tmp.(float64)
+			if !ok {
+				return "", fmt.Errorf("Invalid end_line in function arguments: %v", tmp)
+			}
+			end_line = int(tmp)
+		}
+		var content string
+		tmp, ok = args["content"]
+		if ok {
+			content, ok = tmp.(string)
+			if !ok {
+				return "", fmt.Errorf("Invalid content in function arguments: %v", tmp)
+			}
+		}
+
+		result := fileReplaceLines(path, start_line, end_line, content)
+		ret, err := result.ToJson()
+		if err != nil {
+			return "", fmt.Errorf("Could not serialize result: %v", err)
+		}
+		return ret, nil
+	},
+}
+
+func fileReplaceLines(path string, startLine int, endLine int, content string) api.CallResult {
+	ok, reason := toolutil.IsPathWithinCWD(path)
+	if !ok {
+		return api.CallResult{Message: reason}
+	}
+
+	// Read the existing file's content
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if !os.IsNotExist(err) {
+			return api.CallResult{Message: fmt.Sprintf("Could not read path: %s", err.Error())}
+		}
+		_, err = os.Create(path)
+		if err != nil {
+			return api.CallResult{Message: fmt.Sprintf("Could not create new file: %s", err.Error())}
+		}
+		data = []byte{}
+	}
+
+	if startLine < 1 {
+		return api.CallResult{Message: "start_line cannot be less than 1"}
+	}
+
+	lines := strings.Split(string(data), "\n")
+	contentLines := strings.Split(strings.Trim(content, "\n"), "\n")
+
+	if endLine == 0 || endLine > len(lines) {
+		endLine = len(lines)
+	}
+
+	before := lines[:startLine-1]
+	after := lines[endLine:]
+
+	lines = append(before, append(contentLines, after...)...)
+	newContent := strings.Join(lines, "\n")
+
+	// Join the lines and write back to the file
+	err = os.WriteFile(path, []byte(newContent), 0644)
+	if err != nil {
+		return api.CallResult{Message: fmt.Sprintf("Could not write to path: %s", err.Error())}
+	}
+
+	return api.CallResult{Result: newContent}
+}

pkg/agents/toolbox/read_dir.go

@@ -0,0 +1,100 @@
+package toolbox
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	toolutil "git.mlow.ca/mlow/lmcli/pkg/agents/toolbox/util"
+	"git.mlow.ca/mlow/lmcli/pkg/api"
+)
+
+const READ_DIR_DESCRIPTION = `Return the contents of the CWD (current working directory).
+
+Example result:
+{
+	"message": "success",
+	"result": [
+		{"name": "a_file.txt", "type": "file", "size": 123},
+		{"name": "a_directory/", "type": "dir", "size": 11},
+		...
+	]
+}
+
+For files, size represents the size of the file, in bytes.
+For directories, size represents the number of entries in that directory.`
+
+var ReadDirTool = api.ToolSpec{
+	Name:        "read_dir",
+	Description: READ_DIR_DESCRIPTION,
+	Parameters: []api.ToolParameter{
+		{
+			Name:        "relative_dir",
+			Type:        "string",
+			Description: "If set, read the contents of a directory relative to the current one.",
+		},
+	},
+	Impl: func(tool *api.ToolSpec, args map[string]interface{}) (string, error) {
+		var relativeDir string
+		tmp, ok := args["relative_dir"]
+		if ok {
+			relativeDir, ok = tmp.(string)
+			if !ok {
+				return "", fmt.Errorf("Invalid relative_dir in function arguments: %v", tmp)
+			}
+		}
+		result := readDir(relativeDir)
+		ret, err := result.ToJson()
+		if err != nil {
+			return "", fmt.Errorf("Could not serialize result: %v", err)
+		}
+		return ret, nil
+	},
+}
+
+func readDir(path string) api.CallResult {
+	if path == "" {
+		path = "."
+	}
+	ok, reason := toolutil.IsPathWithinCWD(path)
+	if !ok {
+		return api.CallResult{Message: reason}
+	}
+
+	files, err := os.ReadDir(path)
+	if err != nil {
+		return api.CallResult{
+			Message: err.Error(),
+		}
+	}
+
+	var dirContents []map[string]interface{}
+	for _, f := range files {
+		info, _ := f.Info()
+
+		name := f.Name()
+		if strings.HasPrefix(name, ".") {
+			// skip hidden files
+			continue
+		}
+
+		entryType := "file"
+		size := info.Size()
+
+		if info.IsDir() {
+			name += "/"
+			entryType = "dir"
+			subdirfiles, _ := os.ReadDir(filepath.Join(".", path, info.Name()))
+			size = int64(len(subdirfiles))
+		}
+
+		dirContents = append(dirContents, map[string]interface{}{
+			"name": name,
+			"type": entryType,
+			"size": size,
+		})
+	}
+
+	return api.CallResult{Result: dirContents}
+}

pkg/agents/toolbox/read_file.go

@@ -0,0 +1,73 @@
+package toolbox
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	toolutil "git.mlow.ca/mlow/lmcli/pkg/agents/toolbox/util"
+	"git.mlow.ca/mlow/lmcli/pkg/api"
+)
+
+const READ_FILE_DESCRIPTION = `Retrieve the contents of a text file relative to the current working directory.
+
+Use the file contents for your own reference in completing your task, they do not need to be shown to the user.
+
+Each line of the returned content is prefixed with its line number and a tab (\t).
+
+Example result:
+{
+	"message": "success",
+	"result": "1\tthe contents\n2\tof the file\n"
+}`
+
+var ReadFileTool = api.ToolSpec{
+	Name:        "read_file",
+	Description: READ_FILE_DESCRIPTION,
+	Parameters: []api.ToolParameter{
+		{
+			Name:        "path",
+			Type:        "string",
+			Description: "Path to a file within the current working directory to read.",
+			Required:    true,
+		},
+	},
+
+	Impl: func(tool *api.ToolSpec, args map[string]interface{}) (string, error) {
+		tmp, ok := args["path"]
+		if !ok {
+			return "", fmt.Errorf("Path parameter to read_file was not included.")
+		}
+		path, ok := tmp.(string)
+		if !ok {
+			return "", fmt.Errorf("Invalid path in function arguments: %v", tmp)
+		}
+		result := readFile(path)
+		ret, err := result.ToJson()
+		if err != nil {
+			return "", fmt.Errorf("Could not serialize result: %v", err)
+		}
+		return ret, nil
+	},
+}
+
+func readFile(path string) api.CallResult {
+	ok, reason := toolutil.IsPathWithinCWD(path)
+	if !ok {
+		return api.CallResult{Message: reason}
+	}
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return api.CallResult{Message: fmt.Sprintf("Could not read path: %s", err.Error())}
+	}
+
+	lines := strings.Split(string(data), "\n")
+	content := strings.Builder{}
+	for i, line := range lines {
+		content.WriteString(fmt.Sprintf("%d\t%s\n", i+1, line))
+	}
+
+	return api.CallResult{
+		Result: content.String(),
+	}
+}

pkg/agents/toolbox/util/util.go

@@ -0,0 +1,67 @@
+package util
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// isPathContained attempts to verify whether `path` is the same as or
+// contained within `directory`. It is overly cautious, returning false even if
+// `path` IS contained within `directory`, but the two paths use different
+// casing, and we happen to be on a case-insensitive filesystem.
+// This is ultimately to attempt to stop an LLM from going outside of where I
+// tell it to. Additional layers of security should be considered.. run in a
+// VM/container.
+func IsPathContained(directory string, path string) (bool, error) {
+	// Clean and resolve symlinks for both paths
+	path, err := filepath.Abs(path)
+	if err != nil {
+		return false, err
+	}
+
+	// check if path exists
+	_, err = os.Stat(path)
+	if err != nil {
+		if !os.IsNotExist(err) {
+			return false, fmt.Errorf("Could not stat path: %v", err)
+		}
+	} else {
+		path, err = filepath.EvalSymlinks(path)
+		if err != nil {
+			return false, err
+		}
+	}
+
+	directory, err = filepath.Abs(directory)
+	if err != nil {
+		return false, err
+	}
+	directory, err = filepath.EvalSymlinks(directory)
+	if err != nil {
+		return false, err
+	}
+
+	// Case insensitive checks
+	if !strings.EqualFold(path, directory) &&
+		!strings.HasPrefix(strings.ToLower(path), strings.ToLower(directory)+string(os.PathSeparator)) {
+		return false, nil
+	}
+
+	return true, nil
+}
+
+func IsPathWithinCWD(path string) (bool, string) {
+	cwd, err := os.Getwd()
+	if err != nil {
+		return false, "Failed to determine current working directory"
+	}
+	if ok, err := IsPathContained(cwd, path); !ok {
+		if err != nil {
+			return false, fmt.Sprintf("Could not determine whether path '%s' is within the current working directory: %s", path, err.Error())
+		}
+		return false, fmt.Sprintf("Path '%s' is not within the current working directory", path)
+	}
+	return true, ""
+}

pkg/agents/toolbox/write_file.go

@@ -0,0 +1,71 @@
+package toolbox
+
+import (
+	"fmt"
+	"os"
+
+	toolutil "git.mlow.ca/mlow/lmcli/pkg/agents/toolbox/util"
+	"git.mlow.ca/mlow/lmcli/pkg/api"
+)
+
+const WRITE_FILE_DESCRIPTION = `Write the provided contents to a file relative to the current working directory.
+
+Example result:
+{
+	"message": "success"
+}`
+
+var WriteFileTool = api.ToolSpec{
+	Name:        "write_file",
+	Description: WRITE_FILE_DESCRIPTION,
+	Parameters: []api.ToolParameter{
+		{
+			Name:        "path",
+			Type:        "string",
+			Description: "Path to a file within the current working directory to write to.",
+			Required:    true,
+		},
+		{
+			Name:        "content",
+			Type:        "string",
+			Description: "The content to write to the file. Overwrites any existing content!",
+			Required:    true,
+		},
+	},
+	Impl: func(t *api.ToolSpec, args map[string]interface{}) (string, error) {
+		tmp, ok := args["path"]
+		if !ok {
+			return "", fmt.Errorf("Path parameter to write_file was not included.")
+		}
+		path, ok := tmp.(string)
+		if !ok {
+			return "", fmt.Errorf("Invalid path in function arguments: %v", tmp)
+		}
+		tmp, ok = args["content"]
+		if !ok {
+			return "", fmt.Errorf("Content parameter to write_file was not included.")
+		}
+		content, ok := tmp.(string)
+		if !ok {
+			return "", fmt.Errorf("Invalid content in function arguments: %v", tmp)
+		}
+		result := writeFile(path, content)
+		ret, err := result.ToJson()
+		if err != nil {
+			return "", fmt.Errorf("Could not serialize result: %v", err)
+		}
+		return ret, nil
+	},
+}
+
+func writeFile(path string, content string) api.CallResult {
+	ok, reason := toolutil.IsPathWithinCWD(path)
+	if !ok {
+		return api.CallResult{Message: reason}
+	}
+	err := os.WriteFile(path, []byte(content), 0644)
+	if err != nil {
+		return api.CallResult{Message: fmt.Sprintf("Could not write to path: %s", err.Error())}
+	}
+	return api.CallResult{}
+}