Borrowing it
Nothing to install: this file belongs to BloomBooks/BloomDesktop. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/BloomBooks/BloomDesktop/master/.github/skills/bloom-canvas-tool-testing/SKILL.mdgit clone --depth 1 https://github.com/BloomBooks/BloomDesktopWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/bloombooks/bloomdesktop/bloom-canvas-tool-testing)<a href="https://agentmods.dev/skills/bloombooks/bloomdesktop/bloom-canvas-tool-testing"><img src="https://agentmods.dev/badge/skills/bloombooks/bloomdesktop/bloom-canvas-tool-testing.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00033 | $0.00428 |
| Opus 5 | $0.00016 | $0.00214 |
| Sonnet 5 | $0.00007 | $0.00086 |
| Haiku 4.5 | $0.00003 | $0.00043 |
Grade A, and why
bloom-canvas-tool-manual-testing scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
What it actually says
Scope
Use this skill when the user reports a regression involving Canvas Tool interactions (especially drag/drop from the toolbox onto the page) and asks you to reproduce and verify fixes using a browser.
This skill assumes:
- Bloom is running locally and serving the Edit Tab
- The current page has an element with class
.bloom-canvas - The current page has the Canvas Tool tab available in the toolbox
- The user has started the vite dev server for the frontend code
Primary test URL
http://localhost:8089/bloom/CURRENTPAGE
Reproduction approach (required)
When testing or verifying a UI regression:
- Do not rely only on synthetic JS event dispatch.
- Use browser automation/tools to perform an actual drag/drop gesture.
Finding things
- If your task involves the toolbox, identify that the toolbox iframe (often
.../toolboxContent) and confirm the Canvas Tool tab is selected. - The page we are editing is in an iframe (a
page-memsim-...htm) - On the page, you can locate the canvas we are editing as an element with the
.bloom-canvasclass.
If you are performing drag/drop
- Perform a drag from the toolbox item onto a distinct point on the page (test with multiple drop points).
- Verify outcome by measuring:
- The intended drop point (clientX/clientY over the page frame)
- The created element’s bounding rect and/or
style.left/top - The delta between drop point and element location
- Test with multiple zoom levels and page scaling to confirm consistent behavior
Notes
- Bloom’s edit UI uses multiple iframes; coordinate systems (screen/client/page) often differ between frames.
- Page scaling (
transform: scale(...)) can affectgetBoundingClientRect()values; prefer consistent coordinate spaces when comparing.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 8d ago First seen · 40 lines · 33 tokens per session scan A 1a9f5f1e4f85
bloom-canvas-tool-manual-testing is a skill published in the GitHub repository BloomBooks/BloomDesktop (44 stars, last pushed today), licensed MIT. It adds 33 tokens to every session and 428 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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