Is RateAPI — live US mortgage, auto, HELOC, personal & deposit rates MCP server safe?

Findings (3)

• highWrite-action tools reachable without authenticationauth.open-write
• lowUnusually long tool description (over 2,000 characters)poison.long-description

  tool check_membership_eligibility: …`relative_memberships` carries confirmed current/deceased relative membership scoped to one exact target credit union; one institution is never reused for another. Check whether a user can JOIN specific credit unions (field-of-membership eligibility). Batch-friendly: pass 1-50 credit_union_ids (from get_financing_decision offers, list_credit_unions, or get_credit_union) plus whatever is known about the user (home, worksite, and payroll geography are independent facts; employer, occupation, military_status, school plus school_relationship, and worship are also supported). City facts require their same-role state or a recognized same-role ZIP that uniquely identifies one state, and are accepted only when the closed Census gazetteer resolves them. Returns one row for every requested credit union. Positive outcomes include open_to_anyone, likely_eligible, eligible_via_employer, and eligible_via_military. A school name alone is not a positive signal: school_relationship is required to affirm a typed student, alumni, or school-employee path. Only a graph carrying exact active-publication lineage governs the top compatibility verdict; a publication-less shadow graph remains diagnostic and cannot replace the flat result. A non-match is returned as unknown, with `unknown_reason: fom_completeness_unaffirmed` when the published field-of-membership corpus is not attested complete. The legacy `geo_mismatch` enum value is reserved for wire compatibility and is not emitted by this MCP boundary without a future typed closed-world attestation. Verdicts are guidance based on each credit union's published membership criteria; the final membership determination is always the institution's. Non-matches carry `missing_facts` for the named institutions: the exact question to ask next, the `fact_field` an answer populates, and the institution's own words. A check that returns unknown for all of them and a question for each is a SUCCESSFUL call, not a failure — ask the questions, merge the answers into the same request, and call again. Home geography accepts both the original `zip`/`state`/`county` names and the `home_zip`/`home_state`/`home_county` aliases emitted by `missing_facts`; do not send conflicting values in both forms. Fact fields, in full — supply every one you know: `home_zip`, `home_state`, `home_county`, `home_city`; `work_zip`, `work_state`, `work_county`, `work_city`; `payroll_zip`, `payroll_state`, `payroll_county`, `payroll_city` (payroll can differ from the worksite and is a separate door); `property_zip`, `property_state`, `property_county`, `property_city` (where they OWN property — never inferred from where they live, and an absentee owner qualifies); `facility_zip`, `facility_state`, `facility_county`, `facility_city` (where their business maintains a location); `occupation`; `employer`; `school` plus `school_relationship` (student/alumni/employee — a school name without a relationship affirms nothing); `military_status` plus `military_service_state` (state National Guard doors need the state); `worship`; `family_relation` plus `relative_employers`, `relative_schools`, `relative_associations` (a great many people qualify only through a relative — ask); `applicant_kind` (person/trust/organization/partnership/corporation — some charters admit entities, and a person is never rejected by an entity-only door, only left unknown); and `asserted_org_qualifiers` (narrowings the person asserts about themselves, e.g. "assigned as a recruiter in Arkansas").…

• lowNo source repository listedmaint.no-repo