deep-feature

deep-feature is a command for Claude Code from arc-mcp/arc-1. It costs 0 tokens per session (2,811 once invoked), scanned A, original, MIT.

A command that takes a substantial ARC-1 feature or bug and guides it through research, planning, implementation, live testing, and a pull request. ARC-1 is a tool for working with SAP development systems.

In plain words
What is it for?
Use it for new SAP operations, behavior changes, unclear bugs, or other changes that affect ARC-1’s core safety or integration behavior.
Why use it?
It reduces the risk of building from guessed SAP behavior by requiring important facts to be checked against real sources and systems first.

Command for Claude Code

Part of the arc-1 plugin — 24 skills, 8 commands, 1 MCP server shipped together

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 commands/arc-mcp/arc-1/deep-feature
Clone the repo
git clone --depth 1 https://github.com/arc-mcp/arc-1

Made for: Claude Code.

Or install arc-1, the plugin that ships this one along with the rest of its 24 skills, 8 commands, 1 MCP server.

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 deep-feature

README.md
[![agentmods](https://agentmods.dev/badge/commands/arc-mcp/arc-1/deep-feature.svg)](https://agentmods.dev/commands/arc-mcp/arc-1/deep-feature)
Your own site
<a href="https://agentmods.dev/commands/arc-mcp/arc-1/deep-feature"><img src="https://agentmods.dev/badge/commands/arc-mcp/arc-1/deep-feature.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 2,811 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 $0.00000 $0.02811
Opus 5 $0.00000 $0.01406
Sonnet 5 $0.00000 $0.00562
Haiku 4.5 $0.00000 $0.00281

Measured 4d ago against content hash b15069248f45, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

deep-feature 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 4d 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/commands/deep-feature.md · 122 lines

How it starts

The opening of the file, as written. The whole thing — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Deep Feature — full research → plan → ship lifecycle for ARC-1

The way to start a substantial ARC-1 topic. Drives a feature from deep, cross-source research through a verified plan, autonomous implementation, live testing, and a PR. The whole point: get the full picture from real sources before planning anything — ARC-1's bugs come from planning ADT behavior from memory instead of checking what the system actually does.

Use this for any non-trivial change (new ADT operation, behavior change, bug with unknown root cause, anything SAP-touching). For a tiny surgical edit you already understand, just do it directly.

This replaces the long "first research in detail using docs, other repos, eclipse adt code, adt-ls, adt apis, sap test systems… then plan, review, implement, test, PR" prompt — the sources below are now concrete.


Input

The user gives a feature/bug/topic description (free-form, a gap-analysis item, a GitHub issue, or a run log). If it's vague, ask 1–2 targeted questions, then start researching. Don't over-interview.


The prime directive

No planning until you have the full picture. "Full picture" means you can answer, with evidence: what the ADT endpoint actually is and returns (verified live, not assumed), how SAP's own tools call it, how others implemented it, which ARC-1 code is affected, and how behavior differs across SAP releases. Until then, you are still in Phase 1.

A 200 OK does not mean a filter/type/parameter was honored — ADT silently ignores unknown ones. Verify response content, not just status.


Research Sources (concrete — this is what "docs / other repos / eclipse adt code / adt-ls / adt apis" mean)

All ~/DEV/* repos are read-only references — never modify them. If a path is missing, note it and continue.

Source Where Use it for
ARC-1 project guide CLAUDE.md, INFRASTRUCTURE.md (repo root) Conventions, Key-Files-for-Common-Tasks map, code patterns; the 3 live systems + how to reach them
ARC-1 live research notes docs/research/ — e.g. tabl-append-create-spike-a4h.md, abap-platform-2025-new-adt-apis.md, sapquery-freestyle-capability-matrix.md, adt-transaction-source-write.md; plus the type-code evidence under top-level docs/research/abap-types/ Prior live spikes & ground truth — read these first so you don't re-derive what's already proven
ARC-1 prior plans docs/plans/completed/ How similar features were actually built, tested, and verified
Eclipse ADT — apidoc + endpoint contracts ("eclipse adt code", "adt apis") ~/DEV/arc-1-eclipse-adt/com.sap.adt.core.apidoc-3.58.1/ (SAP's ADT Javadoc), api/01..20-*.md (topic-by-topic endpoint contracts: RAP URIs, lock/create/update/transport, activation/checkruns/inactive, code-nav/completion, where-used, quickfixes/ATC, repository search, DDIC metadata, transports, API release-state, pretty-printer, runtime traces, feature probes), adt-api-is-documented.md, apis.md Exact ADT endpoint URIs, media types, request/response contracts, and observable Eclipse-client behavior. Start here for any new/changed endpoint
SAP ADT language server ("adt-ls code") ~/DEV/arc-1-lsp/vendor/adt-ls, vendor/adt-vscode-*.vsix, docs/adt-ls-reference.md, docs/adt-ls-tool-surface.md, docs/adt-ls-headless-notes.md How SAP's own language server calls ADT; its tool surface; headless behavior — a second independent witness to endpoint contracts
Reference ADT-over-MCP implementations ("adt code" / "other repos") ~/DEV/mcp-abap-adt/, ~/DEV/mcp-abap-adt-fr0ster/ How others implement the same ADT operation — docs/compare approaches, discover endpoints/headers you missed
ABAP language reference ~/DEV/abap-docs/docs/ ABAP keyword/syntax semantics when the feature touches ABAP language constructs
SAP docs / Notes (MCP) sap-docs + sap-notes MCP tools Official documentation, Discovery Center, community, and SAP Notes for known issues/corrections (cite the Note number when a fix depends on it)
Live SAP systems ("sap s4 and 7.5 test system") arc1-cli call <Tool> ..., npm run probe -- --save-fixtures tests/fixtures/probe/<name>, npm run test:integration — creds + recipes in INFRASTRUCTURE.md. Systems: NW 7.50 (npl), S/4HANA 2023 / 758 (a4h), ABAP Platform 2025 / 816 (a4h-2025) Ground truth. What the endpoint ACTUALLY returns, per release. The deciding source when docs and code disagree

Read the full file on GitHub · 122 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. 4d ago First seen · 122 lines · 0 tokens per session scan A b15069248f45

Subscribe to this mod's changes

deep-feature is a command published in the GitHub repository arc-mcp/arc-1 (174 stars, last pushed 3d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 2,811 tokens. 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.