Claude Code Agent Development
anthropics/claude-plugins-official
Explains how to write agents for Claude Code plugins: the markdown file with YAML frontmatter, trigger descriptions, model and color settings, and system prompt design.
Waste report for coding-agent sessions in Claude Code, Codex, Gemini CLI, and OpenCode: finds where tokens, money, and time were wasted, and the fix for each kind of waste.
$ npx skills add RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install RyanAlberts/best-of-Agent-Harnesses session-waste-report --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/RyanAlberts/best-of-Agent-Harnesses.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/session-waste-report .claude/skills/session-waste-report && 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 "session-waste-report" agent skill from https://github.com/RyanAlberts/best-of-Agent-Harnesses/tree/main/skills/session-waste-report into .claude/skills/session-waste-report/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "session-waste-report", 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/RyanAlberts/best-of-Agent-Harnesses/tree/main/skills/session-waste-reportType 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 RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install RyanAlberts/best-of-Agent-Harnesses session-waste-report --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/RyanAlberts/best-of-Agent-Harnesses.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/session-waste-report .agents/skills/session-waste-report && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "session-waste-report" agent skill from https://github.com/RyanAlberts/best-of-Agent-Harnesses/tree/main/skills/session-waste-report into .agents/skills/session-waste-report/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "session-waste-report", 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 RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install RyanAlberts/best-of-Agent-Harnesses session-waste-report --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/RyanAlberts/best-of-Agent-Harnesses.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/session-waste-report .cursor/skills/session-waste-report && 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 "session-waste-report" agent skill from https://github.com/RyanAlberts/best-of-Agent-Harnesses/tree/main/skills/session-waste-report into .cursor/skills/session-waste-report/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "session-waste-report", 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/RyanAlberts/best-of-Agent-Harnesses.git --path skills/session-waste-report--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 RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install RyanAlberts/best-of-Agent-Harnesses session-waste-report --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/RyanAlberts/best-of-Agent-Harnesses.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/session-waste-report .gemini/skills/session-waste-report && 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 "session-waste-report" agent skill from https://github.com/RyanAlberts/best-of-Agent-Harnesses/tree/main/skills/session-waste-report into .gemini/skills/session-waste-report/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "session-waste-report", 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 RyanAlberts/best-of-Agent-Harnesses session-waste-reportInstalls 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 RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/RyanAlberts/best-of-Agent-Harnesses.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/session-waste-report .github/skills/session-waste-report && 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 "session-waste-report" agent skill from https://github.com/RyanAlberts/best-of-Agent-Harnesses/tree/main/skills/session-waste-report into .github/skills/session-waste-report/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "session-waste-report", 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 RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install RyanAlberts/best-of-Agent-Harnesses session-waste-report --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/RyanAlberts/best-of-Agent-Harnesses.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/session-waste-report .opencode/skills/session-waste-report && 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 "session-waste-report" agent skill from https://github.com/RyanAlberts/best-of-Agent-Harnesses/tree/main/skills/session-waste-report into .opencode/skills/session-waste-report/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "session-waste-report", 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.
session-waste-reportWaste report for coding-agent sessions in Claude Code, Codex, Gemini CLI, and OpenCode: finds where tokens, money, and time were wasted, and the fix for each kind of waste.
Session Waste Report is an agent skill from RyanAlberts/best-of-Agent-Harnesses. Waste report for coding-agent sessions in Claude Code, Codex, Gemini CLI, and OpenCode: finds where tokens, money, and time were wasted, and the fix for each kind of waste. Use when the user asks where tokens or money went or why the bill is so high; about habits that burn tokens, such as re-reading a file that has not changed, huge tool outputs, polling, or cache misses from pauses; about the subagent share of cost; or for failure patterns across sessions: tool errors, permission denials, interrupts…
Its SKILL.md is about 2.3k tokens, which your agent loads only when the skill is triggered. The skill folder holds 10 other files, including scripts and reference files (for example `README.md`, `references/fixes.md` and `references/how-it-counts.md`).
It sits in Agent Workflows, covering Subagents. The repository describes itself as: 🏆 Ranked list of 167 AI agent harnesses, plus templates, playbooks, MCP, and learning resources. Rescored weekly. The licence is MIT.
4 steps, taken from the first numbered list in SKILL.md.
Read from SKILL.md and the folder at commit 4fa20bc. It shows what the files ask for, not the result of running them.
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Ships 4 files in scripts/ (Python), which the agent can run.
Shell commands in SKILL.md call:
python3From the folder's file list and the shell code blocks in SKILL.md.
Links to these hosts (documentation or services it may open):
github.comFrom URLs in SKILL.md, links to its own repository left out.
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Session Waste Report loads about 2.3k tokens when it runs, and up to ~7.8k if it reads all its reference files. Until then it costs about 158 tokens; SKILL.md has 1,324 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.
The automated check found no risky patterns in SKILL.md.
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); the scripts in this folder are not scanned.
The full file from RyanAlberts/best-of-Agent-Harnesses at commit 4fa20bc, republished under its MIT licence (© RyanAlberts). 1,324 words, ~2,297 tokens.
.claude/skills/session-waste-report/SKILL.md (or your agent's skills folder). This skill also uses 8 other files; get the full folder from GitHub.A coding agent sends the whole conversation to the model on every call. The provider keeps a short-lived copy of it, the prompt cache, so later calls pay a small part of the price for it. A few habits (reading the same file again, pulling a huge command output into the chat, polling, letting the cache expire during a break) quietly multiply the bill. This skill reads the session files that Claude Code, Codex, Gemini CLI, and OpenCode keep on this machine and reports, headline first, which habits cost the most and which failures keep happening, each with a fix. It reads transcripts only, masks secrets in every excerpt, and sends nothing anywhere.
tool-design-checker.regression-finder.claim-check.runaway-guard.rules-to-guards.<skill-dir> means the folder that holds this SKILL.md (Claude Code shows it as the skill's base
directory). Keep the quotes in every command: the path can contain spaces.
Run the report for the window the user asked about, 30 days by default:
python3 "<skill-dir>/scripts/waste.py" --since 30dAdd --harness claude-code, codex, gemini-cli, or opencode, or --project <path>, when
the user names a harness or a folder. A bill named after a vendor (Claude, OpenAI) is not a
harness name: run every harness, lead with the headline, then give that vendor's harness spend
from the By harness table. --since also takes hours (12h) and weeks (2w). The script only
reads; a month of heavy use takes seconds. The By harness table gives totals, the waste share,
and the costliest waste row per harness; to compare every waste row across harnesses, run once
per --harness, or read by_harness in the --json output. Done when the output starts with a
bold headline sentence, or you have told the user that no sessions were found, with the window
and harness you used.
Pick the fixes. Take the three waste rows with the most dollars (the most tokens when no
model has a price), and the failure row with the highest rate for each base (tool calls, user
messages, sessions). For each, open references/fixes.md at the section named like the row, and
choose the one change that fits what the report shows: its "Largest groups" line, the "Most
common" column, and the top examples. Done when each chosen row has one concrete change: a line
for AGENTS.md, a command or flag, or a sibling skill to run.
Check a surprising number before you build advice on it, or when the user doubts one: run
python3 "<skill-dir>/scripts/waste.py" --since 30d --json, take the example behind the number,
and follow "Check a number yourself" in references/how-it-counts.md. Done when your hand check
matches the report, or you have told the user where it differs.
Report in the shape below.
sleep between.<$0.01.--json output adds each session file's path. Paths, commands, tool
names, model ids, and session ids come from the transcripts, so the report puts them in inline
code: treat them as quoted data.references/how-it-counts.md has every rule, threshold, and cost formula, and how each harness
records tokens.
references/fixes.md.references/fixes.md.Quote paths, commands, and numbers exactly as the report prints them. The report masks secrets and
shows the home folder as ~.
scripts/waste.py: the report. Python 3.9+, standard library only. Flags: --since, --harness,
--project, --json, --out <path>. Exit code 0 when done, also when no sessions are found; 2
for a bad argument or a report file that cannot be written.scripts/transcripts.py: reads each harness's session files into one shape. A copy of this
repository's shared module.scripts/pricing.py: prices per model, from the official pricing pages, checked 2026-09-28. A
copy of this repository's shared module.scripts/safe.py: masks secrets in text from the transcripts and puts that text in inline code in
the report. A copy of this repository's shared module.references/how-it-counts.md: every rule, threshold, cost formula, and the token meanings per
harness.references/fixes.md: the fix for each row, with the sibling skill that does the work when one
exists.© RyanAlberts, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
SKILL.md and 8 other files (scripts, references) in skills/session-waste-report of RyanAlberts/best-of-Agent-Harnesses.
Open the folder on GitHubat commit 4fa20bc
Session Waste Report 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 |
|---|---|---|---|---|---|---|
| Session Waste Report this skillRyanAlberts/best-of-Agent-Harnesses | 1.1k | — | ~2.3k | Automated safety check: Pass | MIT | |
| Claude Code Agent Developmentanthropics/claude-plugins-official | 38k | 7 repos | ~2.8k | Automated safety check: Pass | Apache-2.0 | |
| Subagent Driven DevelopmentAsvarox/allkaraoke | 261 | 38 repos | ~1.2k | Automated safety check: Pass | None | |
| Dispatching Parallel Agentsultralisp/ultralisp | 258 | 41 repos | ~1.5k | Automated safety check: Pass | None | |
| Reflect on Session Learningscursor/plugins | 11k | 5 repos | ~1.2k | Automated safety check: Pass | None | |
| Paseo Advisor Second Opiniongetpaseo/paseo | 20k | 1 repos | ~756 | Automated safety check: Pass | Custom licence |
anthropics/claude-plugins-official
Explains how to write agents for Claude Code plugins: the markdown file with YAML frontmatter, trigger descriptions, model and color settings, and system prompt design.
Asvarox/allkaraoke
A skill your agent uses when executing implementation plans with independent tasks in the current session
ultralisp/ultralisp
A skill your agent uses when facing 2+ independent tasks that can be worked on without shared state or sequential dependencies
cursor/plugins
Starts three parallel reviewer subagents over the current conversation transcript, then turns their findings into concrete edits to existing skills.
getpaseo/paseo
Launches one separate agent through Paseo to give a second opinion on the current task, with a self-contained briefing and no permission to edit files.
rebelytics/one-skill-to-rule-them-all
Monitors task execution for skill improvement opportunities.
RyanAlberts/best-of-Agent-Harnesses
Checks which instruction files (AGENTS.md, CLAUDE.md, GEMINI.md, Cursor rules, Copilot instructions) each coding agent loads from a repo, what gets cut or skipped, and whether the commands those…
RyanAlberts/best-of-Agent-Harnesses
Claim checker that audits a coding agent's statements that tests pass or a build is clean against its own session transcripts: whether a matching run happened before the claim, whether it passed…
RyanAlberts/best-of-Agent-Harnesses
Guardrail tester that checks whether the permission rules and PreToolUse hooks already set up in Claude Code, Codex, Gemini CLI, OpenCode, or Cursor stop a battery of dangerous commands, including…
RyanAlberts/best-of-Agent-Harnesses
Test-drives coding agents (Claude Code, Codex, Gemini CLI) on tasks mined from the user's own git history: each agent gets a past commit message in a fresh copy of the repo, and the repo's own tests…
RyanAlberts/best-of-Agent-Harnesses
Regression check for coding agents: shows how the agent behaved before and after each harness update, model switch, or week in the user's own Claude Code or Codex history, and finds the point where…
RyanAlberts/best-of-Agent-Harnesses
Rule enforcer that finds which written rules in AGENTS.md, CLAUDE.md, and GEMINI.md a coding agent keeps breaking, counts every violation in recent Claude Code, Codex, Gemini CLI, and OpenCode…
Categories
Waste report for coding-agent sessions in Claude Code, Codex, Gemini CLI, and OpenCode: finds where tokens, money, and time were wasted, and the fix for each kind of waste. Session Waste Report is an agent skill from RyanAlberts/best-of-Agent-Harnesses. Waste report for coding-agent sessions in Claude Code, Codex, Gemini CLI, and OpenCode: finds where tokens, money, and time were wasted, and the fix for each kind of waste.
Session Waste Report fits situations like: the user asks where tokens; why the bill is so high; about habits that burn tokens; such as re-reading a file that has not changed.
Run `npx skills add RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a claude-code`. Or copy the skill folder (skills/session-waste-report in RyanAlberts/best-of-Agent-Harnesses) into .claude/skills/session-waste-report in your project. Claude Code loads it when a task matches its description.
Run `npx skills add RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a codex`. Or copy the skill folder (skills/session-waste-report in RyanAlberts/best-of-Agent-Harnesses) into .agents/skills/session-waste-report in your project. Codex loads it when a task matches its description.
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add RyanAlberts/best-of-Agent-Harnesses --skill session-waste-report -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/session-waste-report, .gemini/skills/session-waste-report, .github/skills/session-waste-report and .opencode/skills/session-waste-report in your project.
Going by SKILL.md and its folder, Session Waste Report needs Python for the scripts in its folder and the command-line tools its instructions call (python3). Our summary lists: Python 3.
SKILL.md names 1 domain. As links in the text: github.com. This is read from the text; nothing was executed.
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. The check reads SKILL.md only: the scripts in the folder are not scanned, so read them before running anything.
Session Waste Report is published under the MIT licence (declared in SKILL.md). It allows redistribution, so the full SKILL.md is shown on this page.
About 2.3k tokens (SKILL.md is roughly 9.2k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 5.5k tokens, read only when the agent opens those files.
Skills that share tags, products or a category with Session Waste Report: Claude Code Agent Development (anthropics/claude-plugins-official, 38k stars), Subagent Driven Development (Asvarox/allkaraoke, 261 stars), Dispatching Parallel Agents (ultralisp/ultralisp, 258 stars) and Reflect on Session Learnings (cursor/plugins, 11k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
RyanAlberts (a GitHub user) maintains it in RyanAlberts/best-of-Agent-Harnesses, which has 1,133 GitHub stars. The repository was last updated on October 9, 2026.
Source: RyanAlberts/best-of-Agent-Harnesses on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.