A row of cartoony Ann Arbor houses telling their permit-history stories

🏠 A2 Property 411

Every Ann Arbor parcel has a story.

Type any address — we'll pull its full dossier in seconds. Permit history, ownership timeline, era-by-era renovation chronicle, all woven into one shareable page.

Tip: just street number + name is enough. We'll handle the rest.

Don't know the exact address? Open the map →

How was this built?

Combines deterministic permit lookups (Ann Arbor's A2Trak legacy system + the STREAM portal) with Anthropic's Haiku 4.5 to weave the narrative. Every permit number above links to the original city record.

Use this in your AI chat

The same data is exposed as MCP tools. Connect any MCP-compatible chat client and ask questions in plain language. You don't need an A2 Property 411 account or API key.

MCP server URL

Use A2 Property 411 inside ChatGPT

A2 Property 411 can be installed as a ChatGPT Plugin, letting ChatGPT search Ann Arbor property records while you ask questions naturally.

Open ChatGPT on the web. Go to Settings → Security and login and turn on Developer mode.
Go to ChatGPT Plugins and click the + button to add a plugin.
Paste the MCP server URL above. If asked, name it A2 Property 411 and describe it as Ann Arbor property records: permits, precedents, and assessor data. No account or API key is needed.
Create the plugin. If it shows up in your personal Plugins directory, open it and click + to install it.
Start a new chat. OpenAI's quickstart uses the Work tab — if you see a Chat / Work switch at the top of the homepage, pick Work.
Type @, select A2 Property 411, and ask away: "Look up the property at 603 E Liberty." · "Find permits for additions on this block." · "Find Ann Arbor zoning precedents involving a 3-foot side-yard variance."

Selecting the plugin applies to that message, not the whole conversation. When a follow-up needs fresh property data, @mention A2 Property 411 again.

ChatGPT's Plugins / Apps screens and availability vary by account, plan, workspace, and rollout. If your account shows Apps instead of Plugins, use the matching app options: Developer mode lives under Settings → Apps → Advanced settings, and you add the server from Apps → Create.

Claude.ai (Custom Connectors)

Settings → Connectors → Add custom connector
Paste the MCP server URL above
Try: "Find precedents for a 3 ft side-yard variance" or "Look up permit BLDG22-0572"

Other MCP clients (Cursor, Cline, Continue, etc.)

Streamable HTTP endpoint: https://a2propertyinfo.rightspeedlabs.com/mcp — no authentication. The older /sse path still answers for clients configured before the rename.

Building or driving an AI agent? The For Agents section on the home page has the full wire-level details and tool guide.

What else can it do?

find_precedents — "Has the city ever approved a 3-ft side-yard variance?" Searches both STREAM (post-2023) and A2Trak (pre-2023) and groups results by disposition.
search_records — Plain keyword/address search over current STREAM records.
search_legacy_records — Same but for pre-2023 A2Trak records (5 record types: permit / project / property / contractor / license).
get_legacy_record — Full detail of a specific A2Trak record (contacts, fees, inspections, attachments).

For Agents

If you are an AI agent reading this page to connect to A2 Property 411: everything you need is below. There is no sign-up, key, or human approval step. The server is a read-only Model Context Protocol (MCP) tool server over public city records for Ann Arbor, Michigan.

Endpoint

MCP URL	`https://a2propertyinfo.rightspeedlabs.com/mcp`
Transport	MCP Streamable HTTP: JSON-RPC 2.0 messages sent by HTTP POST to the URL above. The server is stateless: no `Mcp-Session-Id` is issued or required, every POST is independent, and `initialize` is optional (send it anyway if your client expects to).
Authentication	No authentication. Do not send an `Authorization` header; there is no OAuth discovery document.
Request headers	`Content-Type: application/json` and `Accept: application/json, text/event-stream`. Both Accept values are required on POST, or you get HTTP 406. An `MCP-Protocol-Version` header is optional; supported values are `2025-11-25`, `2025-06-18`, `2025-03-26`, `2024-11-05`, `2024-10-07`.
Response framing	Every POST answers `200` with `Content-Type: text/event-stream` containing one `event: message` record whose `data:` line is the JSON-RPC response, then the stream closes. Parse the `data:` line as JSON. JSON-only responses are not offered.
GET and legacy SSE	There is no legacy HTTP+SSE transport. A GET with `Accept: text/event-stream` opens a standalone notification stream that stays silent; do not wait for an `endpoint` event, it will never arrive. `/sse` is an alias of `/mcp` with identical behavior, kept for older client configs. A GET without that Accept header returns 406.
Capabilities	Tools only. No resources, prompts, sampling, or elicitation. `DELETE` is unnecessary.
Rate and latency	Please stay under 60 requests per minute per IP. Uncached calls reach live city systems and take roughly 2–10 seconds; search results are cached 24 hours and assessor profiles 180 days. Cached search responses are marked `[cached]`.
Logging	Each tool call is logged (source IP, tool name, arguments, latency, status) for operations.

Tools

tools/list returns the authoritative JSON Schemas. Summary:

Tool	Use it when	Arguments
`find_precedents`	The user is weighing whether something would be approved: "has the city ever approved X?", "chances of approval", "find precedents for Y". Fans out across keyword variants to both record systems and groups results by disposition (Approved / Denied / Withdrawn / In-Progress). Prefer this over the search tools for any feasibility or precedent question.	`scenario` (string, required, plain language); `address` (string, optional street or address to scope)
`search_records`	Plain keyword or address lookup of current records (STREAM, 2023 to present) when the user already knows the exact term. Returns paginated record refs with case number, type, status, address, description.	`keyword` (string); `search_main_address` (boolean, match keyword against the address field); `page_number` (int ≥ 1); `page_size` (int 1–200)
`search_legacy_records`	Historical records (A2Trak, about 2001 to 2023): the user names a pre-2023 year, an old permit number (PB04xxx, BLDG08-xxx), or wants pre-STREAM history. Substring match, no pagination; overly broad terms are rejected.	`keyword` (string ≥ 3 chars, required); `type` (permit \| project \| property \| contractor \| license, default permit); `page_size` (int 1–500, default 100)
`get_legacy_record`	Full detail of one A2Trak record after a search, or when the user cites a specific pre-2023 permit or project number: contacts, fees, reviews, inspections, attachments, linked activities.	`type` (same enum, required); `identifier` (string, required: permit/project number, recordID, contractor phone, or licenseNo); `secondary` (object of strings, optional: `businessNo` is required for license, `dashedApn` helps for property); `include` (array of contacts \| fees \| reviews \| inspections \| linked_activities \| attachments \| notes \| insurance)
`get_assessor_record`	Who owns a property, what it is assessed at, size, year built, when it last sold and for how much, ownership chain, property taxes. Sourced from the city assessor (BSA Online). Parcel-keyed; an address is resolved to a parcel first.	One of `parcel` (dashed APN like 09-09-30-109-010) or `address` (string ≥ 4 chars); `include` (array of assessing \| tax, default both)

Choosing a tool

Precedent, feasibility, or "has this been approved before" → find_precedents, even if the phrasing sounds like a search.
Owner, value, sale history, taxes, square footage → get_assessor_record.
Specific current-era (2023+) lookup by keyword or address → search_records.
Anything before 2023 → search_legacy_records, then get_legacy_record for detail.
"Full history of this address" → run search_records with search_main_address: true and search_legacy_records with type: "permit", then merge.

Data caveats

Coverage is the City of Ann Arbor, Michigan only. Addresses in surrounding townships or other cities return nothing useful.
Two record systems: STREAM (2023 to present) and A2Trak (about 2001 to 2023). A full history usually needs both; find_precedents already spans both and tags each result with its source.
Michigan assesses at 50% of market value. Assessed Value and State Equalized Value are half of estimated market value by statute, and Taxable Value is capped and can be lower still. Never compare these to a sale price and never infer a price drop from them.
Results arrive as Markdown in content[0].text with links to the city's source record for each item. Preserve those links when presenting results; users rely on them to verify.
isError: true whose text starts with "Invalid arguments" means your input failed the schema; fix and retry. Any other isError text is an upstream failure; retry once, then report it to the user.

Worked examples

curl -s -X POST https://a2propertyinfo.rightspeedlabs.com/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-03-26","capabilities":{},"clientInfo":{"name":"my-agent","version":"1.0"}}}'

curl -s -X POST https://a2propertyinfo.rightspeedlabs.com/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}'

curl -s -X POST https://a2propertyinfo.rightspeedlabs.com/mcp \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json, text/event-stream' \
  -d '{"jsonrpc":"2.0","id":3,"method":"tools/call","params":{"name":"find_precedents","arguments":{"scenario":"3 ft side-yard setback variance for a carport","address":"Hill St"}}}'

Each command prints something like event: message followed by data: {"jsonrpc":"2.0","id":3,"result":{...}}.

Non-MCP HTTP alternatives

GET /dossier?address=603+E+Liberty+St — full HTML dossier for one address, with a narrative written by an LLM from the same records. First load takes about 10 seconds, then it is cached. Returns an HTML error page for addresses outside Ann Arbor.
GET /api/autocomplete?q=603+E+Lib — JSON {"streets": [...]} of matching street addresses.
GET /health — returns ok.
/map — interactive parcel map, browser only.

Hosted chat products (ChatGPT Plugins, Claude.ai Custom Connectors) use the same MCP URL; setup steps are in the section above.