zillow-mcp: Instructions file for Claude Code

CLAUDE.md

zillow-mcp CLAUDE.md is an instructions file for Claude Code from chrischall/zillow-mcp. It costs 3,401 tokens per session, scanned A, original, MIT.

Repository instructions for a Zillow data server that retrieves property information through the user’s signed-in Chrome session.

In plain words
What is it for?
Guiding an agent working on Zillow property searches, property details, and address lookups.
Why use it?
They explain the server’s request routing, available property tools, and expected architecture.

Instructions file for Claude Code

Written for Claude Code: Claude Code plugin machinery. Also seen: reads .claude/ paths; mentions CLAUDE.md.

This is chrischall/zillow-mcp's own configuration. It tells Claude Code how to work on zillow-mcp itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything zillow-mcp configures →

Reuse

Borrowing it

Nothing to install: this file belongs to chrischall/zillow-mcp. 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/chrischall/zillow-mcp/main/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/chrischall/zillow-mcp

Made for: Claude Code.

Wrote this? Show the measurements

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Per session 3,401 This file is loaded in full into every session.
When invoked 3,401 The same file — it is already loaded in full.
Security scan A 1 finding. 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.03401 $0.03401
Opus 5 $0.01700 $0.01700
Sonnet 5 $0.00680 $0.00680
Haiku 4.5 $0.00340 $0.00340

Measured 5d ago against content hash 8340fc70eec9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

zillow-mcp CLAUDE.md scanned grade A with 1 finding 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 5d 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- Don't add IP-rotation or TLS-impersonation libraries. The whole design is "every request rides the user's own browser session via fetchproxy." Adding cycletls / curl-impersonate / Playwright would replace that with a s
CLAUDE.md · 185 lines

How it starts

The opening of the file, as written. The whole thing — 185 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md — zillow-mcp

Guidance for Claude working in this repo.

TL;DR

v0.10.x: Zillow MCP server. Default and only transport: localhost WebSocket via @fetchproxy/server — the companion browser extension is installed separately rather than embedded. Every HTTP call to zillow.com is dispatched through the user's signed-in Chrome tab — each request rides their existing session (cookies, TLS, JS context) exactly as if they'd clicked it themselves.

This is a "Pattern A" fetchproxy MCP (every call rides through fetchproxy), not "Pattern B" (one bootstrap call then direct fetch). Zillow validates each request at the session level, so the in-session routing has to be per-call.

Tool surface

Tool File Endpoint Kind
zillow_search_properties tools/search.ts GET /homes/<location>_rb/?searchQueryState=... SSR read
zillow_get_property tools/properties.ts GET SSR /homedetails/<zpid>_zpid/ (__NEXT_DATA__ gdpClientCache) read
zillow_get_by_address tools/get-by-address.ts GET /homes/<address-slug>_rb/ SSR — shared 4-rung resolver (resolver.ts) read
zillow_resolve_addresses tools/resolve-addresses.ts Batch over the shared resolver (resolver.ts), bridge-concurrency-bounded read
zillow_bulk_get tools/bulk-get.ts fetchPropertyRecord ×N (SSR /homedetails/), concurrency-bounded read
zillow_get_property_photos tools/photos.ts fetchPropertyRecord (SSR) → property.photos[] read
zillow_get_zestimate_history tools/zestimate.ts fetchPropertyRecord (SSR) → homeValueChartData read
zillow_get_price_history tools/history.ts fetchPropertyRecord (SSR) → property.priceHistory read
zillow_get_tax_history tools/history.ts fetchPropertyRecord (SSR) → property.taxHistory read
zillow_compare_properties tools/compare.ts fetchPropertyRecord ×N (SSR), concurrent read
zillow_get_saved_searches tools/saved.ts GET /myzillow/SavedSearches SSR read (auth)
zillow_get_saved_homes tools/saved.ts GET /myzillow/favorites SSR (collectionsResponse[].homes) read (auth)
zillow_get_market_report tools/market.ts GET /home-values/<region>/ SSR read
zillow_calculate_mortgage tools/mortgage.ts (local; no network) read
zillow_calculate_affordability tools/affordability.ts (local; no network) read
zillow_estimate_rent_vs_buy tools/affordability.ts (local; no network) read
zillow_healthcheck tools/healthcheck.ts GET /robots.txt round-trip + bridge status snapshot read
zillow_register_session tools/sessions.ts (local; no network) write (registry)
zillow_set_active_session tools/sessions.ts (local; no network) write (registry)
zillow_get_session_context tools/sessions.ts (local; no network) read

Read the full file on GitHub · 185 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. 5d ago Changed · -1 lines · +22 tokens per session 8340fc70eec9
  2. 9d ago First seen · 186 lines · 3,379 tokens per session scan A 15f30619fe1d

Subscribe to this mod's changes

zillow-mcp CLAUDE.md is an instructions file published in the GitHub repository chrischall/zillow-mcp (0 stars, last pushed today), licensed MIT. It adds 3,401 tokens to every session, about $0.0170 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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