file-server

name	file-server
description	Must invoke when presenting a file to the user. The CharlieBot server has a built-in file browser that serves any file on the host filesystem.
version	1.0.0

File Server

Share files and directories with the user by generating links to the CharlieBot file server. The server serves any file on the host filesystem.

URL Format

<base_url>/absolute_filepath/<absolute-path>

Where <base_url> is the CharlieBot URL resolved from HOST MEMORY (look for the CharlieBot URL entry).

The path after /absolute_filepath/ is the absolute filesystem path with its leading / removed. The prefix names what has to follow it, so a path that dropped its leading segments reads as wrong where it is written. Examples:

Filesystem path	URL
/path/to/trace.json	<base_url>/absolute_filepath/path/to/trace.json
/path/to/results/	<base_url>/absolute_filepath/path/to/results/

The server answers on the alias /files/ as well, which is the prefix links already sent carry and the prefix the web UI builds its own URLs with.

Behavior

• File path: returns the file for download (auto-detected MIME type)
• Directory path: returns an HTML directory listing with clickable entries

When to Use

Whenever you need to present a file to the user (logs, traces, checkpoints, images, configs, and so on), generate the URL instead of dumping file contents into chat. This is especially useful for:

• Large files (traces, logs, pickles)
• Binary files (images, model checkpoints)
• Directories the user may want to browse

Rules

1. Take the path in a link from the current turn's command output: run ls on the exact full path about to be pasted, rather than reconstructing it from memory.

2. Present the link in markdown format: [descriptive text](url)

3. If the file is a Perfetto/Chrome trace (.json trace from training/profiling, or a directory of rank traces), ALWAYS also include a Perfetto viewer link alongside the file link. Read the perfetto skill for how to construct the viewer URL.

   Trace indicators: filename matches trace_rank*.json / *trace*.json, lives under a trace/ or profile/ dir, or the user called it a "trace"/"profile"/"perf capture".

4. Write a raw filesystem path as plain text, path:line, since the CharlieBot UI renders a markdown link around a raw local path as a dead link. The form to wrap in [descriptive text](url) is a file-server URL.

5. An artifact shared beyond Chao (a Slack post, a group report) ships comment-disabled: the comment tray belongs to Chao's own review flow.

HTML Artifacts

Generated HTML artifacts (reports, plans, dashboards) must satisfy:

• Full document with doctype, html, body tags.
• Self-contained: inline CSS/JS. External resources from cdn.jsdelivr.net or unpkg.com only.
• Sandboxing: chat embeds render via srcdoc + sandbox attribute (no access to parent window, cookies, or storage). The plan panel viewer runs same-origin without sandbox because its in-frame comment tray requires same-origin; plan artifact content is trusted master-authored output.
• Aim for well-organized, visually polished pages that present information more densely than markdown allows. Multiple artifacts per response are supported.

Cold-Read Gate

Applied one step before delivery for sitrep, debugging, and explain pages.

Cold-read gate: the page first passes its genre's mechanical DOM assertions, then one zero-context model pass reads the file alone and answers (1) the problem, (2) the conclusion and its epistemic state, (3) what is asked of the reader, (4) the section where the problem first became clear, (5) up to five re-read points, and (6) whether the page answers the chat message that triggered it, quoted verbatim in the probe prompt. Ship when answers (1) through (3) match the author's intent, (4) names the first content section, the epistemic state in (2) matches the page's own labels, and (6) is a yes on every part of the trigger message; a re-read point in (5) naming section 1's forks, or a jump between a fork and another section, also means revise and re-run. Judge on these signals alone.

Invocation (the genre's assertions run first; the probe only fires once every one of them passed):

charliebot artifact check <page-file> --genre <sitrep|debug|explain> --trigger "<trigger message verbatim>"

The six-question prompt, the backend order, and the timeout live in src/core/artifact_check.py; the command prints each tried backend's failure, then the answering backend's id and the six answers verbatim. Exit 0 means every assertion passed; judging the answers stays with the reader of this gate.