Privacy Policy

QueueSim, a ChiAha™ product · Last updated 2026-05-21

The short version

QueueSim is a free queueing simulator. There's no signup, no account, no payment. We collect the minimum metadata needed to run the service, prevent abuse, and keep the lights on. We do not retain the content of your chat conversations unless you explicitly click the Report button on an AI response. We do not sell, rent, or share your data with advertisers, and we do not use your inputs to train AI models. All telemetry is automatically purged after 90 days.

Contents

  1. What we collect
  2. What we do NOT collect
  3. How we use what we collect
  4. Who we share data with
  5. AI model training
  6. Cookies
  7. Retention
  8. Your rights and how to exercise them
  9. International users (GDPR, UK GDPR)
  10. California users (CCPA / CPRA)
  11. Children's privacy
  12. Security
  13. Changes to this policy
  14. Contact

1. What we collect

1.1 Operational telemetry (every visitor)

Every HTTP request to queuesim.com generates standard server logs:

1.2 Simulation inputs you submit at / or /models/{id}

1.3 On-page AI chat (the floating Q bubble on queuesim.com)

If you open the chat widget and send a message, the following happens:

1.4 Public MCP API (queuesim.com/mcp/v1) — the Model Context Protocol server

QueueSim publishes a public Model Context Protocol server at queuesim.com/mcp/v1, listable in the OpenAI app directory, the Anthropic MCP registry, Smithery, Glama, and similar catalogs. It exposes nine read-only, pure-compute tools. Every tool takes abstract queueing parameters and returns simulation results — no tool reads from or writes to any persistent user store, and no tool accepts personally-identifying information as input.

ToolRequired inputsOptional inputsReturns
simulate_mmc arrivalRate (number, > 0, ≤ 200), serviceRate (number, ≥ 0.01, ≤ 10000), servers (integer, 1-50) arrivalDistribution (Exponential/Constant), serviceDistribution (Exponential/Constant/Normal/LogNormal), serviceCoV (0-5), simulationDays (1-30) Per-hour and overall avg wait time (minutes), peak wait, max wait, queue length, utilization, throughput, plus an artifact link to the interactive chart on queuesim.com
simulate_scenario name (one of single, coffee, grocery, callcenter) overrides object with arrivalRate, servers, serviceTimeMinutes, simulationDays (1-30), distributions, and serviceCoV Same shape as simulate_mmc
recommend_staffing arrivalRate, serviceRate, targetAvgWaitMinutes maxServers (1-50), simulationDays (1-30), distributions, serviceCoV Smallest server count whose simulated avg wait does not exceed the target, plus the trial points the search probed
compare_scenarios scenarioA (simulate_mmc-shaped object), scenarioB (same) labelA, labelB Per-scenario inputs and summary, plus the delta on each metric
interpret_result arrivalRate, serviceRate, servers, avgWaitMinutes none A plain-English queueing-theory explanation of the result; pure text computation, no engine call
list_scenarios none none The four preset scenarios with key, title, and description
describe_scenario name (one of single, coffee, grocery, callcenter) none The scenario's full configuration (hourly arrival rates and staffing) plus the list of supported overrides
explain_queueing_theory none none Static textbook-level explainer on M/M/c, Little's Law, utilization, variance
explain_advanced_patterns none none Static explainer covering six complexity patterns beyond M/M/c

What we log per tool invocation: tool name, success/failure, duration in milliseconds, a non-reversible session hash (SHA-256 of your IP + user-agent bucket, first 16 hex chars), the user-agent bucket, the calling MCP client name (e.g. claude.ai, chatgpt, cursor, smithery), and the numerical input parameters you supplied (truncated to 1 KB). These rows go to /data/mcp-tool-calls.jsonl on the application server's encrypted volume and are automatically purged after 90 days. The session hash lets us correlate same-client repeat traffic for abuse forensics within the retention window without storing the IP itself. The input parameters are anonymous numbers (arrival rates, server counts) and do not constitute personal data.

There is no authentication, signup, account, or payment surface on the MCP endpoint. The endpoint is rate-limited per IP to prevent abuse.

1.5 Newsletter signup (only if you opt in)

1.6 Analytics (Google Tag Manager + GA4)

2. What we do NOT collect

3. How we use what we collect

We do not use any of the data we collect for advertising, profiling, or automated decisions that produce legal or similarly significant effects on you.

4. Who we share data with

We do not sell, rent, or trade your data to anyone. We do not "share" your personal information for cross-context behavioral advertising as that term is defined under California law.

5. AI model training

6. Cookies

QueueSim sets only first-party cookies necessary for the analytics integration. We do not set any advertising or cross-site tracking cookies.

CookieSourcePurposeLifetime
_ga Google Analytics 4 (via GTM) Distinguishes unique visitors for aggregate analytics ~2 years (Google default)
_ga_<property-id> Google Analytics 4 (via GTM) Session state for GA4 ~2 years (Google default)
cf_chl_*, cf_clearance (occasional) Cloudflare Turnstile (anti-bot for the chat endpoint) Verifies the chat POST originates from a browser rather than a scripted client Session / short-lived

Browsers in the EU/UK that have not signaled consent for analytics cookies may still receive standard server-log telemetry (IP, UA) but the GA4 cookies will not be set.

7. Retention

All durable QueueSim-side storage is automatically aged out via a background retention service that runs every 24 hours. The 90-day window is enforced by code, not just promised.

WhatWhereRetention
HTTP access logs (IP, UA, path, status) Fly.io platform logs Up to 90 days (Fly's standard log window)
Site-event JSONL (per page hit + simulation run) /data/site-events.jsonl 90 days, enforced by retention cron
MCP tool-call JSONL (per tool invocation, includes anonymous tool inputs) /data/mcp-tool-calls.jsonl 90 days, enforced by retention cron
Chat-history JSONL (aggregate metadata only — no message content) /data/chat-history.jsonl 90 days, enforced by retention cron
Reports (user-submitted chat content via the Report button) /data/reports.jsonl 90 days, enforced by retention cron
In-memory rate-limit state and counters Application memory Resets on every server restart
Newsletter subscriber list ActiveCampaign Until you unsubscribe, after which the address is suppressed
GA4 aggregate analytics Google Analytics property 433243670 14 months (configured GA4 default)

8. Your rights and how to exercise them

Because we do not link logs to an identity, there is usually nothing to "delete" beyond what ages out automatically within 90 days. If you want to exercise a specific right, email queuesim@chiaha.com and include:

We respond within 5 business days. If you submitted a chat Report via the chat widget and want it withdrawn, include the approximate timestamp and the scenario you were on (e.g. "Coffee Shop, May 15 around 2pm Eastern") — the session hash plus the timestamp lets us find your specific row in /data/reports.jsonl and remove it.

9. International users (GDPR, UK GDPR)

QueueSim is operated from the United States. If you are accessing it from the European Economic Area, the United Kingdom, or another jurisdiction with similar data-protection laws, your data is transferred to and processed in the United States.

Our lawful bases for processing (under GDPR Article 6) are:

You have the rights of access, rectification, erasure, restriction, portability, and objection. See Section 8 above for how to exercise any of these. If you are not satisfied with our response, you have the right to lodge a complaint with your local data-protection authority.

10. California users (CCPA / CPRA)

If you are a California resident:

11. Children's privacy

QueueSim is not directed to children under the age of 13. We do not knowingly collect personal information from anyone under 13. If you are a parent or guardian and believe your child has provided us with personal information, contact us at queuesim@chiaha.com and we will delete it.

12. Security

Infrastructure runs on Fly.io with TLS terminating at the edge and encrypted persistent volumes. There are no user passwords or accounts to compromise. The MCP and chat endpoints are rate-limited; the chat endpoint is additionally budget-capped. The retention service automatically purges rows older than 90 days from durable storage. We do not make HIPAA or SOC 2 claims because we do not collect the kind of data those frameworks govern.

13. Changes to this policy

If we make material changes, we'll update this page and revise the "Last updated" date above. Because there are no accounts, there is no email list of users to notify; check back occasionally if it matters to you.

14. Contact

Questions, requests, or concerns: queuesim@chiaha.com. We aim to respond within 5 business days. Mailing address available on request.