Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/band-app/band/implementation-agentnpx skills add band-app/band --skill implementation-agentgit clone --depth 1 https://github.com/band-app/bandWhat 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 | $0.00074 | $0.01994 |
| Opus 5 | $0.00037 | $0.00997 |
| Sonnet 5 | $0.00015 | $0.00399 |
| Haiku 4.5 | $0.00007 | $0.00199 |
Grade A, and why
implementation-agent scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 259 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Implementation Agent
Implements a GitHub issue in a Band workspace. Each run does one piece of work: reads progress from the GitHub issue comment, picks the next task, implements it, commits, pushes, and updates progress. Designed to be called repeatedly — each invocation gets fresh context and picks up where the last one left off.
Prerequisites
- Inside a Band workspace (git worktree managed by Band)
ghCLI authenticated with GitHubbandCLI available- Branch name encodes the issue number:
<issue-number>-<summary>(e.g.,99-task-loop-mode)
Steps
1. Detect Issue and Repo
BRANCH=$(git branch --show-current)
ISSUE_NUMBER=$(echo "$BRANCH" | grep -oE '^[0-9]+')
REPO=$(gh repo view --json nameWithOwner -q .nameWithOwner)
If no issue number is found in the branch name, check the task prompt for a #<number> reference. If still not found, skip issue tracking and just work from the prompt.
Fetch the issue:
gh issue view $ISSUE_NUMBER --repo $REPO
2. Read Progress State
Check for an existing progress comment on the issue:
gh api repos/$REPO/issues/$ISSUE_NUMBER/comments \
--jq '.[] | select(.body | contains("## Implementation Progress")) | {id, body}'
Also check the workspace state:
git log --oneline main..HEAD # What's been committed
git status --porcelain # Any uncommitted work
gh pr list --head $BRANCH --repo $REPO --json number,state,reviewDecision # Existing PR?
3. Route by Current State
Based on what you find, take the appropriate action:
State A — PR exists and is approved: Go to step 8 (Merge and Clean Up).
State B — PR exists with review feedback: Go to step 7 (Handle PR Feedback).
State C — PR exists, CI failing: Go to step 7 (Handle PR Feedback — fix CI).
State D — PR exists, waiting for review: Nothing to do. Print "PR #N is waiting for review" and exit.
State E — No PR, progress comment exists with unchecked items: Go to step 5 (Implement Next Task).
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.
- 2d ago First seen · 259 lines · 74 tokens per session scan A d08b491e7fb9
implementation-agent is a skill published in the GitHub repository band-app/band (5 stars, last pushed 2d ago), licensed MIT. It adds 74 tokens to every session and 1,994 once invoked, about $0.0004 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 2026-08-31.
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bug-triage
Read all open bugs in production/qa/bugs/, re-evaluate priority vs. severity, assign to sprints, surface systemic trends, and produce a triage report. Run at sprint start or when the bug count grows enough to need re-prioritization.