prospec-promote-backfill

prospec-promote-backfill is a skill for Claude Code, Codex from benwu95/prospec. It costs 130 tokens per session (2,673 once invoked), scanned A, original, MIT.

A workflow step that turns a reviewed record of existing behavior into formal change documents. A backfill documents behavior that already exists.

In plain words
What is it for?
Use it to create a proposal, a specification of the differences, and metadata marking the backfill as implemented.
Why use it?
It avoids manually converting an informal backfill draft into the documents needed for later checking and archiving.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

Good fit Use it to create a proposal, a specification of the differences, and metadata marking the backfill as implemented.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/benwu95/prospec/prospec-promote-backfill
Install

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.

Any agent
npx skills add benwu95/prospec --skill prospec-promote-backfill
Clone the repo
git clone --depth 1 https://github.com/benwu95/prospec

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for prospec-promote-backfill

README.md
[![agentmods](https://agentmods.dev/badge/skills/benwu95/prospec/prospec-promote-backfill/github.svg)](https://agentmods.dev/skills/benwu95/prospec/prospec-promote-backfill)
Your own site
<a href="https://agentmods.dev/skills/benwu95/prospec/prospec-promote-backfill"><img src="https://agentmods.dev/badge/skills/benwu95/prospec/prospec-promote-backfill/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for prospec-promote-backfill

Your own site · 80×15
<a href="https://agentmods.dev/skills/benwu95/prospec/prospec-promote-backfill"><img src="https://agentmods.dev/badge/skills/benwu95/prospec/prospec-promote-backfill.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 130 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,673 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00130 $0.02673
Opus 5 $0.00065 $0.01337
Sonnet 5 $0.00026 $0.00535
Haiku 4.5 $0.00013 $0.00267

Measured 5d ago against content hash 9334fc909223, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

prospec-promote-backfill 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 5d 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.

.agents/skills/prospec-promote-backfill/SKILL.md · 141 lines

How it starts

The opening of the file, as written. The whole thing — 141 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Prospec Promote Backfill Skill

Activation

When triggered, briefly describe:

  • That you'll formalize a reviewed backfill-draft.md into the backfill change scaffold — proposal.md + delta-spec.md + metadata.yaml — so it can graduate through prospec-verify (backfill mode) → prospec-archive
  • That this is the single, repeatable draft→scaffold step — it replaces ad-hoc hand conversion and is where the scale: backfill marker is set
  • That backfill is a light scale like quick: it records existing behavior, so there is no plan.md and no tasks.md (nothing to plan, no work to schedule). The scaffold enters the lifecycle directly at status: implemented
  • That it never writes the trust zone (prospec/specs/features/) — prospec archive (the CLI) stays the sole writer

Language Policy

Write each generated document in the language the Constitution's Language Policy rule assigns to its path — change artifacts and their archived summaries in the project's artifact language, the trust zone (Knowledge base, Feature Specs, index) in English. One skill run may write both. Keep code, identifiers, technical terms, and git commit messages in English.

CLI Prerequisite (required)

The prospec CLI is a required file for this skill — its deterministic steps call prospec commands. Probe BEFORE any other step; there is no manual fallback.

  1. Run prospec --version (Bash).
  2. Command not found / not executable → STOP. Ask the user to install the prospec standalone executable — the one-click installer script from the project README (macOS/Linux install.sh, Windows install.ps1) or a release binary from GitHub Releases; prospec is NOT published to npm. Then re-run this skill.
  3. Version older than 2.1.0 → STOP. Report the installed vs required version and ask the user to upgrade, then re-run this skill.

Hand-executing a CLI-owned mutation is NEVER the fallback — that re-introduces the nondeterministic serialization this contract exists to remove.

Read the full file on GitHub · 141 lines

Files

What ships with it

2 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.

Changes

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.

  1. 5d ago Changed 9334fc909223
  2. 9d ago First seen · 141 lines · 130 tokens per session scan A f4744025ddc8

Subscribe to this mod's changes

prospec-promote-backfill is a skill published in the GitHub repository benwu95/prospec (5 stars, last pushed yesterday), licensed MIT. It adds 130 tokens to every session and 2,673 once invoked, about $0.0006 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.