013. A long text becomes a paste marker
- Date
- 2026-10-24
- Agents
- Claude Code, Antigravity CLI
- Measured on
- not recorded
Measured
2026-10-24, Claude Code 2.1.309 and agy 1.4.5, in a pane 120 columns wide.
What was measured
send-keys -l typed text into an empty box. In Claude Code, text of 801
characters or more shows as [Pasted text #N], and as [Pasted text #N +K lines] when it holds K line breaks. Text of 800 characters or fewer stays
text, also on 60 lines. N counts the pastes of the process from 1. The Enter
submits the whole text. The prompt in the UserPromptSubmit hook holds that
text inside <pasted_content id="…"> and </pasted_content id="…">.
agy 1.4.5 draws no marker: a text of 3000 characters stayed text.
Mechanism
A tool that waits to see its own text in the box never sees a long text. It accepts the marker as its text only when the box held no marker after the clear, and the box then holds the marker alone.
Incident
A message of 910 characters failed after the whole send timeout with "Nothing was sent".
Screens
claude/paste, claude/paste-lines, claude/paste-and-text.
Not measured
Other pane widths. Whether the limit of 800 characters depends on the width.
Source
Measured by the tg-bridge project. The text is a summary of its notes, and it holds no host details and no session details.