CaptureRenderer: Capturing Agent Output Renderer

In aisdk: Unified Interface for AI Model Providers

Capturing Agent Output Renderer

Description

A Renderer that records every agent-output event into an in-memory log instead of displaying it – useful for testing, replay, and reusing agent-output logic in non-terminal UIs.

Super class

aisdk::Renderer -> CaptureRenderer

Public fields

log

A list of recorded events, each a list with a type field.

Methods

Public methods

• CaptureRenderer$new()

• CaptureRenderer$process_chunk()

• CaptureRenderer$start_thinking()

• CaptureRenderer$stop_thinking()

• CaptureRenderer$render_tool_start()

• CaptureRenderer$render_tool_result()

• CaptureRenderer$reset_for_new_step()

• CaptureRenderer$events()

• CaptureRenderer$clone()

---

Method new()

Create a capturing renderer with an empty log.

Usage

CaptureRenderer$new()

---

Method process_chunk()

Record a streamed text chunk.

Usage

CaptureRenderer$process_chunk(text, done = FALSE)

Arguments

text

A character chunk, or NULL.

done

TRUE when the text segment is complete.

---

Method start_thinking()

Record the start of a thinking stream.

Usage

CaptureRenderer$start_thinking()

---

Method stop_thinking()

Record the end of a thinking stream.

Usage

CaptureRenderer$stop_thinking()

---

Method render_tool_start()

Record the start of a tool call.

Usage

CaptureRenderer$render_tool_start(name, arguments)

Arguments

name

Tool name.

arguments

Tool arguments.

---

Method render_tool_result()

Record a tool result.

Usage

CaptureRenderer$render_tool_result(
  name,
  result,
  success = TRUE,
  raw_result = NULL
)

Arguments

name

Tool name.

result

The display result.

success

Whether the tool call succeeded.

raw_result

The raw result.

---

Method reset_for_new_step()

Record a ReAct step boundary.

Usage

CaptureRenderer$reset_for_new_step()

---

Method events()

Return the recorded events.

Usage

CaptureRenderer$events()

Returns

A list of recorded events.

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Method clone()

The objects of this class are cloneable with this method.

Usage

CaptureRenderer$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.

aisdk documentation built on May 29, 2026, 9:07 a.m.