Hermes Agent, with rates it can act on.

Set up

Use the CLI through Hermes terminal tools first. Add MCP later only if you want RateAPI to remain in Hermes’ native tool registry.

1. Install once and load the agent protocol

   $Hermes terminal

   Copy

   npm install --global @rateapi/cli
   rateapi agent --json

2. Verify first; authenticate only with approval

   $RateAPI CLI

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   rateapi demo --json
   rateapi doctor --json
    
   # Only after the human approves key creation and secure local storage:
   printf '%s
   ' '{"email":"[email protected]"}' | \
     rateapi login --input @- --confirm-key --json

   The demo is synthetic and free. doctor reuses an environment or stored credential when one exists. The agent must ask separately before key creation/storage and before every metered request.

3. Optional: keep RateAPI as native MCP tools

   $~/.hermes/.env

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   # ~/.hermes/.env  — Hermes resolves ${RATEAPI_API_KEY} from here at connect time
   RATEAPI_API_KEY=rk_your_key_here

   //~/.hermes/config.yaml

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   # ~/.hermes/config.yaml
   mcp_servers:
     rateapi:
       url: "https://mcp.rateapi.dev/mcp?profile=personal"
       headers:
         x-api-key: "${RATEAPI_API_KEY}"

   $Equivalent Hermes command

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   # Optional persistent native MCP connection:
   hermes mcp add rateapi --url "https://mcp.rateapi.dev/mcp?profile=personal" --header "x-api-key:${RATEAPI_API_KEY}"
    
   # ?profile=personal already narrows the 89-tool registry to the consumer
   # surface, in loop order. Drop the query string for the full developer registry.

   CLI and MCP credentials are separate. Use an existing key from the dashboard in the environment that launches Hermes; do not copy the CLI credential file into config. Restart Hermes after adding MCP.

Why an agent needs eligibility before price

The lowest rate in the state and the lowest rate this user can get are different numbers. A real response, captured 2026-08-28 and unedited except for length.

{
  "summary": "Shop Around - Better rates available",
  "resolved_county": { "county": "Mecklenburg", "source": "explicit" },
  "top_offers": [
    {
      "rank": 1, "provider": "State Employees' Credit Union", "product": "30-Year Fixed",
      "rate": "6%", "apr": "6.073%", "points": 0, "monthly_payment": "$2,538",
      "eligibility": { "status": "unknown", "unknown_reason": "charter_type_not_geo_matchable" },
      "eligibility_explanation": { "reason": "Eligibility at State Employees' Credit Union is undetermined; it is not ruled out.", "evidence_url": "https://www.ncsecu.org/join" }
    },
    {
      "rank": 2, "provider": "Piedmont Advantage Credit Union", "product": "30-Year Fixed",
      "rate": "6.125%", "apr": "6.284%", "points": 0, "monthly_payment": "$2,595",
      "eligibility": { "status": "likely_eligible" },
      "eligibility_explanation": { "status": "eligible", "reason": "You qualify for membership at Piedmont Advantage Credit Union.", "source": "graph" }
    },
    {
      "rank": 3, "provider": "Allegacy Credit Union", "product": "30-Year Fixed",
      "rate": "6.625%", "apr": "6.625%", "points": 0.25, "monthly_payment": "$2,689",
      "eligibility": { "status": "unknown", "unknown_reason": "low_confidence_record" }
    }
  ],
  "rate_range": { "min": "6.073%", "max": "6.625%" }
}
// Observed 2026-08-28. Trimmed. The agent leads with #2: it is the best offer behind a door this user can open.
// #1 is not ruled out — a state employee would qualify — so the agent asks, rather than hides it.

{
  "quote": { "rate": 6.625, "apr": 6.625 },
  "percentile": 20, "classification": "plausible",
  "market": { "min": 6.073, "median": 6.8845, "max": 7.197, "count": 40, "as_of": "2026-08-28T04:36:37Z" },
  "note": "This quote beats 80% of the 40 live NC 30-year mortgage offers we track (median 6.885%).",
  "better_offers": [
    { "credit_union_name": "State Employees' Credit Union", "apr": 6.073, "apr_delta_bps": 55,
      "estimated_monthly_savings": 144.23, "can_you_join": "unknown" },
    { "credit_union_name": "Piedmont Advantage Credit Union", "apr": 6.284, "apr_delta_bps": 34,
      "estimated_monthly_savings": 89.52, "can_you_join": "yes" }
  ],
  "share_url": "https://rateapi.dev/rate-check?product=mortgage&state=NC&rate=6.625&term=360&zip=28202"
}
// Observed 2026-08-28. "can_you_join: yes" is the field that turns a percentile into a plan.

The first conversation

Prompts that exercise the whole loop. The CLI routes each request through its capability catalog; a persistent MCP connection exposes the corresponding native tools.

Because Hermes keeps memory, the facts from the first prompt — ZIP, employer — carry into every later one. Tell it once.

1

“I live in 28202 and work at Atrium Health. Which credit unions can I actually join, and what is the best 30-year rate among them for a $420k purchase with a 740 score?”

2

“I was quoted 6.625% on a 30-year in North Carolina. Is that good, and can I do better somewhere that will have me?”

3

“Watch NC 30-year rates and tell me when something I can join drops below 6.1%.”

4

“Which credit unions have a branch within 10 miles of 28202, and what do they charge on a 60-month used auto loan?”

A real run, captured 2026-08-28

Hermes Agent v0.20.6 on Gemini 3.6 Flash, captured with the persistent MCP option before the CLI-first onboarding shipped. The data contract and loop are the same; unedited except for length.

Tool sequence

find_eligible_credit_unions → check_membership_eligibility → find_product_rates_near_zip → find_credit_unions_near_zip → get_financing_decision → get_credit_union — 21 calls, 51 seconds. Eligibility first, price second, without being told to.

Its answer, on the best rate

“If you or an immediate family member have a connection to NC state employment, SECU offers the lowest rate at 6.000% (6.073% APR). Otherwise, Piedmont Advantage Credit Union offers the best directly eligible rate for Mecklenburg County residents.”

On the quote (second prompt)

“Your quote sits in the top 20th percentile of the 30-year fixed mortgage market in North Carolina… YES — Piedmont Advantage Credit Union: 6.125% rate / 6.284% APR (0 points). Cuts your APR by 34 basis points… Membership Eligibility: 100% YES. PACU has a community charter covering Mecklenburg County.” — and it pasted the share_url so the user could re-check live. 5 calls, 19 seconds.

What it got from the tools, not from memory

The Truliant, Skyla and Allegacy membership paths it listed (American Consumer Council association, family of member) appear in the get_credit_union and eligibility results in the session export — grounded, with the reason for each verdict.

What the agent will and will not do

These constraints ship in every tool description, so the agent inherits them without prompting.

Every rate is attributed and dated

“6.284% APR at Piedmont Advantage Credit Union, observed 2026-08-28, per its published rate sheet.” Never a bare number; never a rate outside the freshness window.

Unknown is never no

When eligibility cannot be confirmed the agent says so, with the reason, and asks the one question that would resolve it. It does not hide the institution.

No approvals

Published pricing is not an offer. Membership first, then the lender underwrites. The agent finds reachable offers and shows the evidence.

No national average

Benchmarks are medians across the credit unions tracked, labelled as such.

Credit unions only

About 2,950 with fresh rates across 55 states and territories. Not banks, not indices, not non-US lenders — the agent says so rather than guessing.

No credit pull

Eligibility is decided from published rules and the user’s own facts. Score, income and debt are never requested to decide who they can join.

Frequently asked

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