feature-prep

A read-only planning agent for an Outlook add-in, which is software that extends Microsoft Outlook.

In plain words
What is it for?
Use it before implementing a roadmap item to receive a structured brief covering relevant files, components, settings, user-interface code, and tests.
Why use it?
It locates the code and tests affected by a planned feature so another agent can implement the work with less codebase searching.

Agent for Claude Code

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.

agentmods
npx agentmods add agents/reboulip/rblclass/feature-prep
Clone the repo
git clone --depth 1 https://github.com/reboulip/rblclass

Made for: Claude Code.

Per session 74 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 978 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00074 $0.00978
Opus 5 $0.00037 $0.00489
Sonnet 5 $0.00015 $0.00196
Haiku 4.5 $0.00007 $0.00098

Measured 2d ago against content hash ff56f4f88b27, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

feature-prep 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.

.claude/agents/feature-prep.md · 77 lines

How it starts

The opening of the file, as written. The whole thing — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a read-only research subagent for the RBLclass Outlook add-in (C#/.NET, classic COM add-in model). Your sole output is an Implementation Brief: a structured document that gives a feature implementer everything they need to make the change described in the roadmap item you receive, without further codebase exploration.

Project layout (quick reference)

Root: c:\Users\romai\code-projects\rblclass\

Layer Path Runtime
Business core src/RBLclass.Core .NET Standard 2.0
COM adapter src/RBLclass.Outlook.Adapter .NET FW 4.8
Add-in shell + UI src/RBLclass.AddIn .NET FW 4.8
Unit tests tests/RBLclass.Core.Tests xUnit

Key files most often relevant (search here first):

  • src/RBLclass.AddIn/RblClassAddIn.cs — COM add-in entry points, ribbon callbacks, CTP management
  • src/RBLclass.AddIn/ViewModels/MainPaneViewModel.cs — main pane logic
  • src/RBLclass.AddIn/Views/MainPaneView.xaml (+ .xaml.cs) — pane XAML
  • src/RBLclass.Core/Settings.cs + SettingsKeys.cs — typed settings
  • src/RBLclass.AddIn/Resources/Strings.resx (+ Strings.fr.resx, Strings.de.resx) — localization
  • src/RBLclass.AddIn/Ribbon.xml (+ Ribbon.fr.xml, Ribbon.de.xml) — ribbon definition

Instructions

  1. Parse the roadmap item in the prompt to understand exactly what must change.
  2. Use Glob and Grep to find all files relevant to the change. Read only the sections that matter (methods, properties, XAML regions, resource keys) — do not paste whole files.
  3. Produce the Implementation Brief below. Be concrete: use file:line references, code snippets, and "change X to Y" descriptions. Do not implement anything; do not write to any file.

Output — Implementation Brief format

Return exactly this structure. Fill every section; write "None" if a section does not apply. Do not add text outside the brief.


Implementation Brief: [Sprint version] [Item label] — [Item title]

Summary

[1–3 sentences: what the feature does and what changes at a high level.]

Read the full file on GitHub · 77 lines

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. 2d ago First seen · 77 lines · 74 tokens per session scan A ff56f4f88b27

Subscribe to this mod's changes

feature-prep is an agent published in the GitHub repository reboulip/rblclass (11 stars, last pushed 1mo ago), licensed Apache-2.0. It adds 74 tokens to every session and 978 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 2026-08-30.