Agent Browser CLI
vercel-labs/agent-browser
Browser automation CLI for AI agents. Use when the user needs to interact with websites, including navigating pages, filling forms, clicking buttons, taking…
“Resolve "yesterday" to a concrete ISO date range relative to your run time — yesterday. Returns inclusive civil dates plus exact UTC instants so you have temporal context without…”
Install Yesterday Date Resolver
$ npx skills add HarnessMD/munder-difflin --skill yesterday -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install HarnessMD/munder-difflin yesterday --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/HarnessMD/munder-difflin.git skills-src && mkdir -p .claude/skills && cp -r skills-src/resources/skills/yesterday .claude/skills/yesterday && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "yesterday" agent skill from https://github.com/HarnessMD/munder-difflin/tree/main/resources/skills/yesterday into .claude/skills/yesterday/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "yesterday", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/HarnessMD/munder-difflin/tree/main/resources/skills/yesterdayType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add HarnessMD/munder-difflin --skill yesterday -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install HarnessMD/munder-difflin yesterday --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/HarnessMD/munder-difflin.git skills-src && mkdir -p .agents/skills && cp -r skills-src/resources/skills/yesterday .agents/skills/yesterday && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "yesterday" agent skill from https://github.com/HarnessMD/munder-difflin/tree/main/resources/skills/yesterday into .agents/skills/yesterday/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "yesterday", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add HarnessMD/munder-difflin --skill yesterday -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install HarnessMD/munder-difflin yesterday --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/HarnessMD/munder-difflin.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/resources/skills/yesterday .cursor/skills/yesterday && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "yesterday" agent skill from https://github.com/HarnessMD/munder-difflin/tree/main/resources/skills/yesterday into .cursor/skills/yesterday/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "yesterday", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/HarnessMD/munder-difflin.git --path resources/skills/yesterday--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add HarnessMD/munder-difflin --skill yesterday -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install HarnessMD/munder-difflin yesterday --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/HarnessMD/munder-difflin.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/resources/skills/yesterday .gemini/skills/yesterday && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "yesterday" agent skill from https://github.com/HarnessMD/munder-difflin/tree/main/resources/skills/yesterday into .gemini/skills/yesterday/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "yesterday", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install HarnessMD/munder-difflin yesterdayInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add HarnessMD/munder-difflin --skill yesterday -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/HarnessMD/munder-difflin.git skills-src && mkdir -p .github/skills && cp -r skills-src/resources/skills/yesterday .github/skills/yesterday && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "yesterday" agent skill from https://github.com/HarnessMD/munder-difflin/tree/main/resources/skills/yesterday into .github/skills/yesterday/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "yesterday", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add HarnessMD/munder-difflin --skill yesterday -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install HarnessMD/munder-difflin yesterday --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/HarnessMD/munder-difflin.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/resources/skills/yesterday .opencode/skills/yesterday && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "yesterday" agent skill from https://github.com/HarnessMD/munder-difflin/tree/main/resources/skills/yesterday into .opencode/skills/yesterday/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "yesterday", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
yesterday- GitHub stars
- 8.6k
- Token cost
- ~290 tokens
- SKILL.md length
- 103 words
- Files
- 1
- Skills in repo
- 7
- Repo updated
- First seen
- Licence
- MIT
At a glance
- Calls node
About this skill
“Resolve "yesterday" to a concrete ISO date range relative to your run time — yesterday. Returns inclusive civil dates plus exact UTC instants so you have temporal context without computing dates by hand. Read-only: no writes, no network. Use before a task scoped to yesterday (daily reports, "what changed yesterday").”
Yesterday Date Resolver is a skill in HarnessMD/munder-difflin (8.6k stars). Its SKILL.md is about 290 tokens. Licence: MIT.
Requirements
- Pre-approved tools (allowed-tools): Bash
What it can do on your machine
Read from SKILL.md and the folder at commit 2c64612. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves these tools, so the agent can use them without asking each time:
Bash
From allowed-tools in the SKILL.md frontmatter.
Runs code
Shell commands in SKILL.md call:
node
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Yesterday Date Resolver loads about 290 tokens when it runs. Until then it costs about 82 tokens; SKILL.md has 103 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check: notes
The automated check noted patterns worth knowing about, such as sudo or a known installer.
- NotePre-approves every shell command (allowed-tools: Bash)SKILL.md
allowed-tools: Bash
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from HarnessMD/munder-difflin at commit 2c64612, republished under its MIT licence (© HarnessMD). 103 words, ~290 tokens.
Download SKILL.mdSave it as
.claude/skills/yesterday/SKILL.md (or your agent's skills folder).- name
- yesterday
- description
- Resolve "yesterday" to a concrete ISO date range relative to your run time — yesterday. Returns inclusive civil dates plus exact UTC instants so you have temporal context without computing dates by hand. Read-only: no writes, no network. Use before a task scoped to yesterday (daily reports, "what changed yesterday").
- allowed-tools
- Bash
/yesterday
Get the concrete date range for yesterday by running the bundled resolver:
node "$AGENT_DIR/.claude/skills/temporal/when.mjs" yesterdayIt prints a human-readable line plus a JSON record:
start/end— inclusive civil dates (YYYY-MM-DD) in your local timezonestartUtc/endExclusiveUtc— the same window as a half-open[start, end)range of exact UTC instants, for timestamp-based queriesdays,timezone,asOf— the span, your timezone, and when this resolved
Use the returned dates as the time bounds for the task at hand. Do not derive
dates by hand — this resolver is the source of truth. For the full window list
or an arbitrary range (e.g. last45days, last6months), see the /temporal skill.
© HarnessMD, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in resources/skills/yesterday of HarnessMD/munder-difflin.
Open the folder on GitHubat commit 2c64612
Compare with similar skills
Yesterday Date Resolver next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Yesterday Date Resolver this skillHarnessMD/munder-difflin | 8.6k | — | ~290 | Automated safety check: Notes | MIT | |
| Agent Browser CLIvercel-labs/agent-browser | 44k | 24 repos | ~864 | Automated safety check: Pass | Apache-2.0 | |
| Agent Browserquran/quran.com-frontend-next | 1.9k | 40 repos | ~3.3k | Automated safety check: Pass | None | |
| Web Access via Browser CDPeze-is/web-access | 9.1k | 4 repos | ~2.2k | Automated safety check: Pass | MIT | |
| Dev Browser AutomationMemTensor/MemOS | 12k | 3 repos | ~1.7k | Automated safety check: Pass | Apache-2.0 | |
| Agent ReachPanniantong/Agent-Reach | 94k | — | ~1.4k | Automated safety check: Pass | MIT |
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Resolve, start or resume, implement, review, test, and publish exactly one existing ai-tdesktop task by short slug or full dated id, including rare blocked retries and split-required results.
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Categories
Questions about Yesterday Date Resolver
How do I install Yesterday Date Resolver in Claude Code?
Run `npx skills add HarnessMD/munder-difflin --skill yesterday -a claude-code`. Or copy the skill folder (resources/skills/yesterday in HarnessMD/munder-difflin) into .claude/skills/yesterday in your project. Claude Code loads it when a task matches its description.
How do I install Yesterday Date Resolver in Codex?
Run `npx skills add HarnessMD/munder-difflin --skill yesterday -a codex`. Or copy the skill folder (resources/skills/yesterday in HarnessMD/munder-difflin) into .agents/skills/yesterday in your project. Codex loads it when a task matches its description.
Can I use Yesterday Date Resolver in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add HarnessMD/munder-difflin --skill yesterday -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/yesterday, .gemini/skills/yesterday, .github/skills/yesterday and .opencode/skills/yesterday in your project.
What does Yesterday Date Resolver need to run?
Going by SKILL.md and its folder, Yesterday Date Resolver needs the command-line tools its instructions call (node). Its frontmatter pre-approves these tools: Bash.
Does Yesterday Date Resolver access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Yesterday Date Resolver safe to install?
Our automated static check of SKILL.md found notes only (pre-approves every shell command (allowed-tools: bash)), nothing it rates as a warning. It is not a guarantee. Review the folder before installing.
What licence does Yesterday Date Resolver use?
Yesterday Date Resolver is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Yesterday Date Resolver use?
About 290 tokens (SKILL.md is roughly 1.2k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Yesterday Date Resolver?
Skills that share tags, products or a category with Yesterday Date Resolver: Agent Browser CLI (vercel-labs/agent-browser, 44k stars), Agent Browser (quran/quran.com-frontend-next, 1.9k stars), Web Access via Browser CDP (eze-is/web-access, 9.1k stars) and Dev Browser Automation (MemTensor/MemOS, 12k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Yesterday Date Resolver?
HarnessMD (a GitHub organization) maintains it in HarnessMD/munder-difflin, which has 8,603 GitHub stars. The repository holds 7 skills in this directory. The repository was last updated on October 9, 2026.
Source: HarnessMD/munder-difflin on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.