render

Documentation

Overview

Package render provides emoji-driven terminal rendering for the odek agent loop.

It produces structured output for each phase of the ReAct cycle: thinking, tool calls, tool results, and the final answer. When a Renderer is nil or disabled, no output is produced — this keeps the programmatic API silent and the CLI colorful.

Design

• Zero dependencies. Uses ANSI escape codes directly.
• Emoji icons as visual anchors (🧠 🔧 ✅ ❌).
• Color detection: respects NO_COLOR env var and tty detection.
• Truncation: tool output is collapsed to one line to keep the terminal scannable during multi-step tool chains.
• Maintainable: each rendering method is self-contained; adding a new event type requires one constant + one method.

Index

• func ColorEnabled() bool
• type Event
  • func (e Event) String() string
• type Renderer
  • func New(w io.Writer, color bool) *Renderer
  • func (r *Renderer) Error(err error)
  • func (r *Renderer) FinalAnswer(text string)
  • func (r *Renderer) Iteration(n, maxN int, latency time.Duration, inTokens, outTokens int, turn int)
  • func (r *Renderer) Start(task string)
  • func (r *Renderer) Thinking(text string)
  • func (r *Renderer) ToolCall(name, args string)
  • func (r *Renderer) ToolResult(output string)
  • func (r *Renderer) WithModel(name string) *Renderer

Functions

func ColorEnabled

func ColorEnabled() bool

ColorEnabled returns true when the terminal supports ANSI colors and the user hasn't set NO_COLOR.

Types

type Event

type Event int

Event identifies a point in the agent loop lifecycle. Programmatic consumers can type-switch on Event values.

const (
	// IterStart marks the beginning of an iteration cycle.
	IterStart Event = iota
	// Thinking is the model's reasoning text before tool calls.
	Thinking
	// ToolCall is a tool invocation requested by the model.
	ToolCall
	// ToolResult is the output from a completed tool call.
	ToolResult
	// FinalAnswer is the model's final response (no tool calls).
	FinalAnswer
	// Error is a non-fatal error during the loop.
	Error
)

func (Event) String

func (e Event) String() string

type Renderer

type Renderer struct {
	// contains filtered or unexported fields
}

Renderer writes formatted agent loop output to an io.Writer. The zero value is usable but won't produce any output — call New() to create a properly initialized Renderer.

func New

func New(w io.Writer, color bool) *Renderer

New creates a Renderer that writes to w. If color is false, ANSI escape codes are stripped from the output.

func (*Renderer) Error

func (r *Renderer) Error(err error)

Error prints a non-fatal loop error with a cross emoji.

func (*Renderer) FinalAnswer

func (r *Renderer) FinalAnswer(text string)

FinalAnswer prints the model's concluding response with a checkmark emoji.

func (*Renderer) Iteration

func (r *Renderer) Iteration(n, maxN int, latency time.Duration, inTokens, outTokens int, turn int)

Iteration prints the cycle header with optional turn statistics and turn number. When turn > 0, shows "Turn N" in the header. When latency > 0 or tokens are reported, a compact stats suffix appears on the same line: [1,247 in · 342 out · 4.1s]

func (*Renderer) Start

func (r *Renderer) Start(task string)

Start prints the session header with task preview.

func (*Renderer) Thinking

func (r *Renderer) Thinking(text string)

Thinking prints the model's reasoning text with a brain emoji.

func (*Renderer) ToolCall

func (r *Renderer) ToolCall(name, args string)

ToolCall prints a tool invocation with wrench emoji, name, and compact args.

func (*Renderer) ToolResult

func (r *Renderer) ToolResult(output string)

ToolResult prints a one-line summary of the tool output in gray. Long output is collapsed to the first line + ellipsis to keep the terminal readable during multi-step tool chains.

func (*Renderer) WithModel

func (r *Renderer) WithModel(name string) *Renderer

WithModel sets the model name displayed in iteration headers.