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 commands/arc-mcp/arc-1/implement-featuregit clone --depth 1 https://github.com/arc-mcp/arc-1What 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 | $0.00000 | $0.02556 |
| Opus 5 | $0.00000 | $0.01278 |
| Sonnet 5 | $0.00000 | $0.00511 |
| Haiku 4.5 | $0.00000 | $0.00256 |
Grade A, and why
implement-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 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 — 252 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Implement Feature
Quality-first implementation workflow for ARC-1 features. Guides you through research, planning, test-driven development, and documentation updates.
Input
The user provides a feature description — either a reference to a gap analysis item (e.g., from docs/compare/08-dassian-adt-feature-gap.md), a GitHub issue, or a free-form description.
SAP auth guidance:
- When touching auth (Layer A or Layer B), read
docs_page/enterprise-auth.md#coexistence-matrixfirst. ThevalidateConfigfail-fast rules insrc/server/config.tsare the authoritative source — extend them if adding a new combination.
Ask the user for:
- Feature description (required) — what to implement
- Scope (optional) — small/medium/large, helps calibrate effort
If only a description is given, infer scope from the description and proceed.
Phase 1: Research & Understand
Before writing any code, understand the full picture.
1a. Read project guidelines
Read CLAUDE.md to refresh on project conventions, code patterns, and key file mappings.
1b. Understand existing code in the affected area
Based on the feature description, identify and read all relevant source files. Use the "Key Files for Common Tasks" table in CLAUDE.md as a starting point:
| Task | Files |
|---|---|
| Add new read operation | src/adt/client.ts, src/handlers/read.ts, src/handlers/tools.ts |
| Add new tool type | src/handlers/tools.ts, src/handlers/schemas.ts, src/handlers/dispatch.ts |
| Add safety check | src/adt/safety.ts |
| Add XML parser rule | src/adt/xml-parser.ts |
| Add error handling | src/adt/errors.ts, src/handlers/dispatch.ts |
| Add transport feature | src/adt/transport.ts, src/handlers/transport.ts |
| Add DDIC domain/data element write | src/adt/ddic-xml.ts, src/adt/crud.ts, src/handlers/write.ts, src/handlers/schemas.ts, src/handlers/tools.ts |
| Add context feature | src/context/compressor.ts, src/context/deps.ts |
| Add CDS impact analysis context | src/adt/cds-impact.ts, src/adt/codeintel.ts (findWhereUsed), src/handlers/context.ts (SAPContext action="impact"), tests/unit/adt/cds-impact.test.ts |
| Add diagnostic | src/adt/diagnostics.ts, src/handlers/diagnose.ts |
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 · 252 lines · 0 tokens per session scan A 6a93fa4de1dc
implement-feature is a command published in the GitHub repository arc-mcp/arc-1 (174 stars, last pushed 2d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 2,556 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.
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