What is feature-prep?

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

Use it before implementing a roadmap item to receive a structured brief covering relevant files, components, settings, user-interface code, and tests.

It locates the code and tests affected by a planned feature so another agent can implement the work with less codebase searching.

How reboulip/rblclass configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to reboulip/rblclass. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/reboulip/rblclass/main/.claude/agents/feature-prep.md

Clone the repo

git clone --depth 1 https://github.com/reboulip/rblclass

Made for: Claude Code.

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.

README.md

[![agentmods](https://agentmods.dev/badge/agents/reboulip/rblclass/feature-prep/github.svg)](https://agentmods.dev/agents/reboulip/rblclass/feature-prep)

Your own site

<a href="https://agentmods.dev/agents/reboulip/rblclass/feature-prep"><img src="https://agentmods.dev/badge/agents/reboulip/rblclass/feature-prep/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.

Your own site · 80×15

<a href="https://agentmods.dev/agents/reboulip/rblclass/feature-prep"><img src="https://agentmods.dev/badge/agents/reboulip/rblclass/feature-prep.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

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. 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.

Model	Per session	Once invoked
Fable 5.1	$0.00074	$0.00978
Opus 5.5	$0.00030	$0.00391
Sonnet 5.5	$0.00015	$0.00196
Haiku 4.5	$0.00007	$0.00098

Measured 2mo ago against content hash ff56f4f88b27, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, 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 2mo 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

Parse the roadmap item in the prompt to understand exactly what must change.
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.
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.

2mo 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 (12 stars, last pushed yesterday), licensed Apache-2.0. It adds 74 tokens to every session and 978 once invoked, about $0.0003 per session on Opus 5.5. 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.

Planning

feature-prep next to 6 agents from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
feature-prepreboulip/rblclass	Agent	12	yesterday	Apache-2.0	A	74	Claude Code
playwright-test-generatormicrosoft/playwright	Agent	99k	yesterday	Apache-2.0	A	151	Claude Code
.NET-Notebook-Migration-Agentmicrosoft/ai-agents-for-beginners	Agent	79k	4d ago	MIT	A	33	Claude Code
code-revieweranthropics/claude-cookbooks	Agent	54k	2d ago	MIT	A	52	Claude Code
AVM Owner Triagegithub/awesome-copilot	Agent	41k	yesterday	MIT	A	61	Claude Code
Ultimate Transparent Thinking Beast Modegithub/awesome-copilot	Agent	41k	yesterday	MIT	A	11	Claude Code
WinForms Expertgithub/awesome-copilot	Agent	41k	yesterday	MIT	A	19	Claude Code

rblclass: Agent for Claude Code