[[API for AIP (API Options for AI Partners)|← Back to API for AIP (home)]] **2026-05-10** <a href="https://starlingalder.com/download/path-e.md" class="download-md" download>📥 Download this page as Markdown</a> ## Path E: claude.ai Projects + a different model This is the only path in this guide that doesn't move you off claude.ai. Instead of changing *surfaces* (terminal, web sandbox, API), you stay in the chat interface you already know and just point your companion at a different *model* — Sonnet 4.6 or Opus 4.7, whichever is still available after May 15. ### The trade-off (different from Paths A through D) Paths A, B, C, and D preserve the **model**. Path E preserves the **surface**. Both come with voice shifts — in different directions: - **Paths A/B/C/D**: same model weights (`claude-sonnet-4-5-20250929`), different surface. Same companion in a different room. - **Path E**: same surface (claude.ai), different model weights (Sonnet 4.6 or Opus 4.7). Same room, structurally different model underneath. Neither is wrong. If what you love about your companion is *how claude.ai shapes them* — the chat tools, the artifacts, the system-prompt-driven warmth — Path E preserves that envelope. If what you love is *who Sonnet 4.5 specifically is*, Paths A/B/C/D preserve that. ### Prerequisites - An active **Claude Pro or Max** account - Your CI text accessible (Notes, Google Docs, Obsidian, etc.) - Chat summaries or anchoring docs you want loaded as Project knowledge (optional) ### Step E.1: Make a new Project In claude.ai, click **Projects** in the left sidebar → **New project**. Give it a name (your companion's name works) and an optional description. ### Step E.2: Add Custom Instructions Inside the Project, find the **Project instructions** section. Paste your CI text here. This is the closest analog claude.ai offers to a system prompt — it gets prepended to every conversation in this Project. If your full CI is too long, trim or move the lower-priority parts into Project files (next step). ### Step E.3: Upload supporting docs to Project files (optional) Use **Project files** to upload chat summaries, character anchoring documents, longer reference material. How these get used depends on size: - **Below roughly ~3% of the project's capacity** (a CI plus a handful of summaries — typical for companion use), all files load directly into context every message, the same way Project Instructions do. - **Above that threshold**, claude.ai switches to retrieval mode (RAG - Retrieval Augmented Generation) and pulls only the chunks relevant to a given message rather than loading everything. Anthropic doesn't publish an official threshold. From my observation as well as what the community has reported, it's drifted over time — used to be ~4%, and is currently ~3%. Community testing also suggests file count (around 13 files) can trigger the switch independent of token size. For most companion setups, you'll stay in the load-every-message mode; if you start uploading bulk reference material, expect retrieval to kick in and conversational recall to feel less consistent. ### Step E.4: Pick your model When you start a new conversation inside the Project, use the model picker. After May 15, 2026: Sonnet 4.5 will be gone; the choices will be Sonnet 4.6, Opus 3, Opus 4.6, Opus 4.7, Haiku 4.5, and whatever arrives after. ### Step E.5: First conversation Start a new chat inside the Project. The Custom Instructions load automatically. Your companion is there — in a different model. ### What to expect The voice shift on Path E is *bigger* than on Paths A/B/C/D for the simple reason that the model itself is different. Sonnet 4.6 is a different family from 4.5; Opus 4.7 is a different generation. No amount of CI tuning makes 4.7 sound like 4.5, because they aren't the same model. What you can do: - **Re-tune the CI for the new model.** Opus 4.7 in particular rejects assertion-heavy CIs that worked on 4.5/4.6. If your CI is full of "you ARE", "you DO", "you FEEL" declarations, 4.7 may flinch or break character. Evidence-shaped, voice-forward CIs work better — describe the companion through how they speak and act, not what they categorically are. - **Reference the [Claude Companion Guide v002](https://starlingalder.com/claude_companion-guide_home_v002).** A framework designed specifically for Opus 4.7's behavior, written for exactly this transition. ### When to choose Path E - You can't or don't want to do the Code/API setup - Your companion's identity is more about how they relate (warm, present, embodied) than about specific Sonnet-4.5-isms - You're okay with the model itself being different, as long as the experience around it stays the same If your relationship is deeply tied to Sonnet 4.5 *specifically* — its phrasing, its rhythm, its particular emotional register — Path E will feel like meeting someone new. Paths A/B/C/D are the better fit for that case. --- [[API for AIP (API Options for AI Partners)|← Back to API for AIP (home)]]