Have Opus one-shot custom Obsidian plugins for your own vault
He found Opus good at one-shotting Obsidian plugins without even being shown a sample, so he made a few just for himself that only fit his own vault structure.
Source
bad_username on Hacker News · 2026-10-20
Written in our own words. Credit to the original author. Link checked 2026-10-23.
What they did
He found Opus good at one-shotting Obsidian plugins without even being shown a sample, so he made a few just for himself that only fit his own vault structure.
Result (as claimed)
Each personal plugin costs only a few dollars to make, so publishing them isn't worth it.
Tools they used
Cost: Claude Opus 5.5: from $4 in / $20 out per 1M tokens.
Set it up
Define the job
Say exactly what you want done and what the agent may and may not do on your behalf.
Share only what is needed
Give Claude Opus 5.5 the minimum files or access required. Avoid sharing passwords in chat when a safer login flow exists.
Review the plan
Ask the agent to show its plan or draft before it acts, and approve each step that has real consequences.
Check the result
Confirm the outcome yourself (order placed, request sent, document understood) and keep a record.
Copy the full setup prompt
Paste into your agent and it will walk you through the setup, asking before anything that sends, posts or spends.
You are helping me set up this AI use case end to end in Claude Code. Goal: Have Opus one-shot custom Obsidian plugins for your own vault What the original author did: He found Opus good at one-shotting Obsidian plugins without even being shown a sample, so he made a few just for himself that only fit his own vault structure. Reported result (as claimed by the author): Each personal plugin costs only a few dollars to make, so publishing them isn't worth it. Source: https://news.ycombinator.com/item?id=50162575 Tools they used: Claude Opus 5.5, Obsidian Category: Personal & life Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Codex. Goal: Have Opus one-shot custom Obsidian plugins for your own vault What the original author did: He found Opus good at one-shotting Obsidian plugins without even being shown a sample, so he made a few just for himself that only fit his own vault structure. Reported result (as claimed by the author): Each personal plugin costs only a few dollars to make, so publishing them isn't worth it. Source: https://news.ycombinator.com/item?id=50162575 Tools they used: Claude Opus 5.5, Obsidian Category: Personal & life Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Grok Bot. Goal: Have Opus one-shot custom Obsidian plugins for your own vault What the original author did: He found Opus good at one-shotting Obsidian plugins without even being shown a sample, so he made a few just for himself that only fit his own vault structure. Reported result (as claimed by the author): Each personal plugin costs only a few dollars to make, so publishing them isn't worth it. Source: https://news.ycombinator.com/item?id=50162575 Tools they used: Claude Opus 5.5, Obsidian Category: Personal & life Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
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Guides for this use case
How to build private apps just for yourself with AI · How to build an AI second brain and personal wiki · How to use AI agents with Obsidian and your notes · How to use Claude Code skills and plugins
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