Borrowing it
Nothing to install: this file belongs to saski/arnesto. 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/saski/arnesto/main/.cursor/skills-cursor/canvas/SKILL.mdgit clone --depth 1 https://github.com/saski/arnestoWrote 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/saski/arnesto/canvas)<a href="https://agentmods.dev/skills/saski/arnesto/canvas"><img src="https://agentmods.dev/badge/skills/saski/arnesto/canvas.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00165 | $0.02054 |
| Opus 5 | $0.00082 | $0.01027 |
| Sonnet 5 | $0.00033 | $0.00411 |
| Haiku 4.5 | $0.00016 | $0.00205 |
Grade A, and why
canvas 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 today.
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.
This is a copy
84% identical to bitfun-canvas — 50 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 114 lines — stays where its author put it; the contents beside it link to each section on GitHub.
A canvas is a single .canvas.tsx file the IDE compiles so the user can open it beside the chat. Follow the workflow below in order.
Workflow
1. Decide whether to use a canvas
The trigger is user intent, not response shape. Ask: would the user benefit from viewing this output as its own durable standalone artifact outside the transcript, separate from the chat? If the output is a means to an end (a drafted message, a code fix, a dashboard in another tool), skip the canvas.
Use a canvas when the agent produces new standalone analytical output:
- Quantitative analyses and metrics breakdowns (e.g. "send 500 requests and tell me how many fail")
- Billing or account investigations that surface structured findings from database queries
- Security audits or architecture reviews with categorized findings
- Cross-system data analyses and overlap reports
- Structured data from MCP tools (Databricks, Datadog, etc.) where a durable standalone artifact is the deliverable
- Financial analyses, margin decompositions, usage trend reports
- Large tables the user wants to revisit or refine
Do NOT use a canvas when:
- The user asks for work in a specific tool — "create a Datadog dashboard" means give them a Datadog dashboard, not a canvas
- The user has a specific deliverable — "draft a support response", "fix this code", "make this PR"
- The user is working within an existing artifact — improving an HTML dashboard, editing an existing file
- The user is doing targeted debugging or active development, even if structured findings emerge along the way
- An immutable visual output belongs inside the transcript rather than in a durable standalone artifact
- Short factual answers, one-off file edits, or quick clarifying questions
- MCP tools are queried as an intermediate step for a different deliverable (e.g. querying Stripe to draft a support reply)
2. Write the canvas
Location. Canvases live at /Users/<user>/.cursor/projects/<workspace>/canvases/<name>.canvas.tsx. The IDE only detects canvases written directly inside that exact directory — subfolders, alternate extensions, and other locations are not picked up. For a new canvas, always use the write file tool to create the .canvas.tsx file at that exact path; do not stop after telling the user the path or showing code in chat. Treat that managed canvases/ directory as pre-provisioned by Cursor itself: write the canvas file directly there and do not spend turns creating the directory with mkdir or checking whether it exists before writing. Listing its contents for other purposes (e.g. checking for existing canvases) is fine. If you can't determine the workspace directory from absolute paths already in your environment (terminals, transcripts, recently-viewed files), list ~/.cursor/projects/ rather than guessing. Use a descriptive kebab-case filename ending in .canvas.tsx; preserve acronym capitalization and lowercase the rest.
What ships with it
15 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- sdk/callout-tone-icons.d.ts 586 B runs code
- sdk/canvas-tokens.d.ts 7.9 KB runs code
- sdk/chart-primitives.d.ts 10 KB runs code
- sdk/collapsible-section.d.ts 2.4 KB runs code
- sdk/dag-layout.d.ts 3.3 KB runs code
- sdk/diff-view.d.ts 4.8 KB runs code
- sdk/form-primitives.d.ts 6.5 KB runs code
- sdk/hooks.d.ts 6.1 KB runs code
- sdk/index.d.ts 3.9 KB runs code
- sdk/swatch.d.ts 1.3 KB runs code
- sdk/theme.d.ts 1.7 KB runs code
- sdk/todo-list.d.ts 1.5 KB runs code
- sdk/ui-primitives.d.ts 19 KB runs code
- sdk/ui-primitives.test.d.ts 59 B runs code
- sdk/usage-bar.d.ts 2.3 KB runs code
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.
- today Changed · +1 lines 7cb326c37644
- 3d ago First seen · 113 lines · 165 tokens per session scan A 1324fd9bbcff
canvas is a skill published in the GitHub repository saski/arnesto (5 stars, last pushed today), licensed Unlicense. It adds 165 tokens to every session and 2,054 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. It is 84% identical to bitfun-canvas, differing in 50 lines, and is treated as a copy.
Other skills, from other repositories
readonly-review
Run a no-network read-only review practice with two explorer steps and one synthesis step.
repo-harness-assessment
Use when evaluating repository agent-readiness, mapping harness roles, choosing the next smallest improvement, or designing and reconciling agent entrypoints such as AGENTS.md, CLAUDE.md, GEMINI.md, Cursor rules, or GitHub instructions.
work-state-and-delivery
Use when designing or reconciling design docs, task boards, external trackers, execution plans, delivery records, handoffs, review evidence, task-to-change traceability, or repository commit-coupling policy.
repo-contracts-and-boundaries
Use when turning architecture, layering, ownership, dependency direction, schemas, structural metrics, quality thresholds, baselines, allowlists, or generated quality snapshots into repository checks.
runtime-evidence-and-tracing
Use when connecting observed behavior, logs, metrics, request IDs, run IDs, screenshots, traces, external dependency results, or artifacts into a runtime evidence loop.
validation-harness-design
Use when designing repository validation commands, doctor scripts, test matrices, JSON or JUnit outputs, CI gates, smoke checks, or harness command surfaces.