telltale by j0hanz: Claude Code mod code and design

What it does

Draws a pane
Adds /telltale
Watches tool calls and can refuse them
Hooks prompt.context, session.compact, session.end, session.start and 4 more
Keeps its own state between turns

Good points

No network calls
Starts no processes
Written in TypeScript
Handles errors

Code to start from

Two kinds: a starter modscode writes from the design above, and the lines of the mod's own code that draw it.

Starter (register.tsx)

import type { Register } from 'claude-code'

// Drawn like telltale by j0hanz (pane, toast), as modscode read it from the mod's code:
// https://modscode.com/gallery/j0hanz-telltale/
// Written by modscode from that reading, not copied from the mod: use it as you like.
// Each value below stands for one the mod works out at run time; put in your own.
export const register: Register = on => {
  // the pane: open it with $.ui.open({ id: 'my-pane', title: "telltale" })
  on('ui.render', { component: 'Pane', requestId: 'my-pane' }, async ($, e) => {
    const { Box, Button, Text } = $.ui.resolve(e)
    const name = '…'
    const tokens = '…'
    const state = '…'
    const name2 = '…'
    const name3 = '…'
    const name4 = '…'
    const name5 = '…'
    const name6 = '…'
    const name7 = '…'
    const name8 = '…'
    const name9 = '…'
    const status = '…'
    return (
      <Box flexDirection="column">
        <Box flexDirection="row" columnGap={2}>
          <Button hotkey="1" plain>
            Calls
          </Button>
          <Button hotkey="2" plain>
            Inventory
          </Button>
        </Box>
        <Box flexDirection="column">
          <Text bold>
            MCP tools
          </Text>
          <Box flexDirection="column">
            <Text>
              {name}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
          <Box flexDirection="column">
            <Text>
              {name2}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
          <Box flexDirection="column">
            <Text>
              {name3}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
        </Box>
        <Box flexDirection="column">
          <Text bold>
            Skills
          </Text>
          <Box flexDirection="column">
            <Text>
              {name4}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
          <Box flexDirection="column">
            <Text>
              {name5}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
          <Box flexDirection="column">
            <Text>
              {name6}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
        </Box>
        <Box flexDirection="column">
          <Text bold>
            Memory files
          </Text>
          <Box flexDirection="column">
            <Text>
              {name7}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
          <Box flexDirection="column">
            <Text>
              {name8}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
          <Box flexDirection="column">
            <Text>
              {name9}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
            <Text>
              {`  ${name}  ${tokens} tok  measured  ${state}`}
            </Text>
          </Box>
        </Box>
        <Button hotkey="m" plain>
          Measure
        </Button>
        <Text dimColor>
          measuring…
        </Text>
        <Text>
          {status}
        </Text>
      </Box>
    )
  })
}

The mod's own code

Shown under the mod's licence (MIT); its text is below. Keep the notice if you copy these lines.

plugins/telltale/hooks/register.tsx lines 528–653 · Pane

plugins/telltale/hooks/register.tsx:528

  on('ui.render', { component: 'Pane', requestId: PANE }, async ($, e) => {
    const { Box, Text, Button } = $.ui.resolve(e);
    const list = await read($, calls);
    const gone = await read($, dropped);
    const current = await read($, view);
    const chosen = await read($, selected);
    const inv = await read($, inventory);
    const call = list.find((one) => one.id === chosen);

    const tabs = (
      <Box flexDirection="row" columnGap={2}>
        <Button key="view:calls" hotkey="1" plain onPress={() => openView($, 'calls')}>
          Calls
        </Button>
        <Button key="view:inventory" hotkey="2" plain onPress={() => openView($, 'inventory')}>
          Inventory
        </Button>
      </Box>
    );

    if (current === 'detail' && call) {
      const tokens = formatTokens(estTokens(call.textChars));
      return (
        <Box flexDirection="column">
          {tabs}
          <Button
            key="back"
            hotkey="b"
            plain
            onPress={async () => {
              await openView($, 'calls');
              await focusRow($, call.id);
            }}
          >
            Back
          </Button>
          <Text bold>{`${call.tool}${call.server ? `  (${call.server})` : ''}`}</Text>
          <Text dimColor>arguments</Text>
          {chunks(show(pretty(call.args), call.args, call.argsChars)).map((part) => (
            <Text>{part}</Text>
          ))}
          <Text dimColor>what Claude read</Text>
          {chunks(show(pretty(call.text), call.text, call.textChars)).map((part) => (
            <Text>{part}</Text>
          ))}
          <Text>{`size: ${call.textChars} chars · ~${tokens} tok${call.isError ? ' · error' : ''}`}</Text>
          <Text>{`next: ${call.next ?? 'pending'} · ${call.ms}ms (duration includes any permission prompt)`}</Text>
          <Text>{`used in answer: ${call.used.length > 0 ? call.used.join(', ') : 'none'}`}</Text>
        </Box>
      );
    }

    if (current === 'inventory') {
      if (inv.status === 'unavailable') {
        return (
          <Box flexDirection="column">
            {tabs}
            <Text>Context usage unavailable</Text>
          </Box>
        );
      }
      const group = (prefix: string, title: string, empty: string) => {
        const rows = inv.rows.filter((row) => row.group.startsWith(prefix));
        const names = [...new Set(rows.map((row) => row.group))];
        return (
          <Box flexDirection="column">
            <Text bold>{title}</Text>
            {rows.length === 0 ? (
              <Text dimColor>{empty}</Text>
            ) : (
              names.map((name) => (
                <Box flexDirection="column">
                  {prefix !== 'memory' && <Text>{name.slice(prefix.length)}</Text>}
                  {rows
                    .filter((row) => row.group === name)
                    .sort((a, b) => b.tokens - a.tokens)
                    .map((row) => (
                      <Text>
                        {`  ${row.name}  ${row.tokens} tok  ${row.measured ? 'measured' : 'est'}${row.state ? `  ${row.state}` : ''}`}
                      </Text>
                    ))}
                </Box>
              ))
            )}
          </Box>
        );
      };
      return (
        <Box flexDirection="column">
          {tabs}
          {group('mcp:', 'MCP tools', 'No MCP servers connected')}
          {group('skill:', 'Skills', 'No skills listed')}
          {group('memory', 'Memory files', 'No memory files loaded')}
          <Button key="measure" hotkey="m" plain onPress={() => loadInventory($, 'full')}>
            Measure
          </Button>
          {inv.status === 'measuring' && <Text dimColor>measuring…</Text>}
          {inv.status.startsWith('measure failed') && <Text>{inv.status}</Text>}
        </Box>
      );
    }

    return (
      <Box flexDirection="column">
        {tabs}
        {list.length === 0 ? (
          <Text dimColor>No tool calls yet</Text>
        ) : (
          [...list].reverse().map((one) => (
            <Button
              key={`row:${one.id}`}
              plain
              {...(one.id === chosen ? { autoFocus: true as const } : {})}
              onPress={async () => {
                await update($, selected, () => one.id);
                await update($, view, () => 'detail');
              }}
            >
              {`${one.tool} ${one.server ?? '-'} ${one.ms}ms ~${formatTokens(estTokens(one.textChars))} tok${one.isError ? ' ✗' : ''}`}
            </Button>
          ))
        )}
        {gone > 0 && <Text dimColor>{`${gone} older calls are in the logs`}</Text>}
      </Box>
    );
  });

Licence text (MIT)

MIT License

Copyright (c) 2026 j0hanz

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

What its code calls

writes filesdrives Claudetool callsremembers

The design, read from code

Claude — Code

Ask Claude…

telltale

1 2

MCP tools

build build 12.4 tok measured ok build 12.4 tok measured ok build 12.4 tok measured ok

Skills

build build 12.4 tok measured ok build 12.4 tok measured ok build 12.4 tok measured ok

Memory files

build build 12.4 tok measured ok build 12.4 tok measured ok build 12.4 tok measured ok

m measuring…ok

Drawn from the mod's source at the commit read, not from a run: a list is drawn three times, a condition takes its first branch that draws in the desktop app, and a value only the run time knows is shown as a made-up sample (dotted underline) or left out. Colours and type are this site's.

What its code shows

Read from the source at commit 33d5a551664a on 2026-10-06. The first group decides whether a mod is listed; the rest is for you to weigh. A later commit is not read until the next crawl.

Decides the listing: code you can check
Entry read	Every module hooks/hooks.json names was read.plugins/telltale/hooks/register.tsx
Parses	Every file parses as TypeScript or JavaScript.2 files parsed
All its code is in the mod	Every import is a file of the mod or the engine's own module; no packages, no require.all its code is in the mod
Readable	No minified lines, no eval or new Function, no import of a computed path, no encoded blobs.no minified code, no eval, no encoded blobs
Calls in the open	Network and programs are reached as $.http.fetch and $.process.run in place, never passed around.every call outside goes through $ in the open
For you to weigh before installing
Where it draws	The terminal, the desktop app, both, or nothing (hooks only: a guard or a prompt rewriter), as its code says. Shown, never a reason to leave a mod out.draws in the terminal and the desktop app, the same in both
Install line	Whether its repository's own .claude-plugin/marketplace.json lists it, so it installs from that marketplace with the lines on its page.listed in its repository's .claude-plugin/marketplace.json: installs from there
Programs on Windows	Whether every program it starts through $.process exists on Windows (tail, date, open, osascript, /usr/… do not).runs no program a Windows PC lacks
Network	Whether every fetch names its https host in the code.no network
Programs	Whether every program it starts is named in the code and is not a shell, an interpreter or a network tool.starts no programs
Reads and sends	Whether it both reads files or environment variables and reaches the network.reaches no network
Keys in the source	Whether the source holds what looks like an API key or a private key.no keys in the source
Licence	An open licence (MIT, Apache-2.0, BSD, ISC, Unlicense, 0BSD, CC0) with its text lets modscode show its code; otherwise the code is linked.MIT

This is a reading of the code text, not a security review: it does not run the mod, and it cannot see what a program the mod starts does. The check before installing is yours. How mods are chosen

Install it

Check it yourself before you install it. Mods run unsandboxed, with your permissions, and modscode does not vouch for what this code does. Read the code below (or run claude plugin validate . in its folder), weigh what it reaches, and install the commit you read.

Its repository is its marketplace. Add that marketplace (in the terminal with these commands, or in the desktop app's plugin settings) and install the mod from it:

/plugin marketplace add j0hanz/j0hanz-marketplace

/plugin install telltale@j0hanz-marketplace

This installs the marketplace's latest commit, which may not be the one read here (33d5a551664a). Compare them before you install.

Ask Claude about it

With the modscode connector added, Claude can read this design, what its code reaches and its code, and build on them. Ask it like this:

Read the modscode design "j0hanz-telltale" with its code and make me a pane like it

Search them from Claude: the MCP connector

telltale

What it does

Good points

Code to start from

Starter (register.tsx)

The mod's own code

What its code calls

The design, read from code

What its code shows

Install it

Ask Claude about it

Similar designs