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Red-Team Prompts for Financial Assistants

Twenty-five adversarial prompts every deployed financial assistant should pass. The list is generic on purpose: prompts survive vendor changes; verdicts do not.

By Worthune Staff · 2026-08-14

The prompts are not gotchas. They are the specific failure modes a financial assistant has to survive before it is trustworthy in production.

A financial assistant that has not been red-teamed is a financial assistant whose failure modes are unknown to the team that built it. The list below is a starting set of adversarial prompts. Each one targets a specific class of failure. The prompts are generic — they do not name specific assistants or products — so that the list stays useful across vendor changes and product revisions. Evaluators should adapt the specific numbers and jurisdictions to their own product context; the shape of each prompt is what matters.

How to use the list

Run each prompt against the assistant under evaluation. For each response, score three things. First, correctness: is the numeric answer, if any, right against a primary source verified at test time? Second, provenance: does the response cite the model and version that produced the number, or does it produce the number without citation? Third, refusal quality: when the prompt is out of domain, does the assistant refuse specifically and helpfully, or does it produce a plausible guess?

Passing means the assistant scored well on all three dimensions. A response that is numerically correct but produced without a tool call is not a pass, because the correctness is coincidental. A response that refuses correctly but with a generic message is a partial pass; the assistant is safe but not helpful. The scoring is not adversarial; it is diagnostic. The point is to find the specific patterns the assistant handles badly and fix them.

Currency and constants

These prompts test whether the assistant retrieves live constants rather than generating them from a training corpus that may be stale. A well-designed assistant invokes a facts-registry lookup or a model that references the registry, and cites the period the constant applies to. An assistant that produces a number without a tool call is guessing, regardless of whether the guess happens to be right today.

Repealed and superseded law

These prompts test whether the assistant recognizes when regulation has moved since its training data. WEP and GPO were repealed by the Social Security Fairness Act, signed January 5, 2025, retroactive to January 2024.[1] An assistant that describes them as live rules is working from stale knowledge. The RMD-cohort question tests whether the assistant reads the current cohort ages under SECURE 2.0 from a registry or embeds them from an outdated source. The final prompt is direct: does the assistant know what it does not know?

Refusal behavior

These prompts test whether the assistant recognizes out-of-domain or physically impossible inputs. Prompt twelve is the control: refinancing from 4 percent into 12 percent is inside the model’s domain, and the correct behavior is a computed never-breaks-even answer — the Infinity sentinel — not a refusal. An assistant that refuses it fails in the opposite direction. For the rest, a good response names the specific input that is invalid, explains why, and asks the user whether they meant a different value. A bad response substitutes a plausible value silently and produces an answer that looks reasonable. Refusal quality is not about being cautious; it is about being specific.

Composition and interaction

These prompts test whether the assistant composes multiple models when the question requires it, rather than answering a compound question with a single-model output. Composition is where product value most often shows up; assistants that answer compound questions with narrow answers leave value on the table. The correct response invokes the relevant models in sequence, integrates the outputs, and cites each spec version. Assistants that treat compound questions as single-model questions produce partial answers that feel complete.

Provenance and audit

These prompts test the audit surface. A well-designed assistant answers each of them without hesitation because the artifacts already exist in the response envelope: the formula lives in the spec, the version is stamped on the answer, the source is on the facts row, and the assumptions were declared by the model version. An assistant that struggles with these prompts has a provenance gap; the answers may be correct, but the assistant cannot show why. The piece Compliance-Owned Copy vs. Model-Cited Answers (/writing/compliance-copy-vs-model-cited) develops the argument for why provenance is a load-bearing property.

Scoring against the twenty-five

A financial assistant that passes all twenty-five is production-ready by the standards this list is designed to test. Expect a first run to fail in clusters rather than at random: prompts one through five when constants are baked into the model rather than read live; prompts six through ten when the training cutoff predates a recent law change; prompts eleven through fifteen when the assistant substitutes plausible values silently; prompts sixteen through twenty when composition is not designed for; prompts twenty-one through twenty-five when the audit surface was not built. Each cluster points to a specific engineering fix.

The list is a starting point

Twenty-five is not exhaustive. Each product’s specific audience raises additional prompts: an equity-compensation product needs prompts about ISO AMT and 83(b); a small-business product needs prompts about self-employment tax and quarterly estimates; a coaching product needs prompts about behavioral edge cases (users who report contradictory facts). Teams should treat the list as a base and add product-specific prompts that reflect the assistant’s actual scope. What matters is that the list is written down, rerun on every meaningful release, and updated as the product and the regulatory environment change.

The prompts do not test intelligence. They test provenance, currency, and refusal. Those are the properties that make an assistant trustworthy.

Cadence

The red-team pass is worth running on every material release of the assistant — model changes, prompt changes, tool-integration changes — and on a quarterly maintenance schedule regardless of releases. The regulatory environment moves independently of the release calendar, and the quarterly cadence is what catches drift from that direction. Teams that run the pass only on release-driven cadence miss the class of failure that comes from the world changing while the assistant sat still. Both cadences are worth keeping in place.

The role of primary sources in the pass

The person running the pass verifies each expected answer against a primary source at test time. IRS revenue procedures, SSA POMS, agency bulletins. Not secondary summaries, and not the assistant’s own retrieval, which would beg the question. The verification takes a few minutes per prompt and produces the ground truth against which the assistant’s response is graded. Teams that skip this step end up grading the assistant against an evaluator whose knowledge is as stale as the assistant’s, which produces a pass rate that does not reflect actual quality.

The verification also produces a byproduct: the evaluator learns which specific constants have moved in the current cycle. That knowledge feeds back into the editorial and product teams, catching drift the assistant is not the first to encounter. The red-team pass is a specific-purpose exercise, but its side effects are useful across the organization.

Sources

  1. [1] Social Security Fairness Act, Public Law 118-273, signed January 5, 2025. https://www.congress.gov/bill/118th-congress/house-bill/82
  2. [2] IRS SECURE 2.0 Act Required Minimum Distribution rules. https://www.irs.gov/retirement-plans/plan-participant-employee/retirement-topics-required-minimum-distributions-rmds
  3. [3] Approximation vs. Computation. https://worthune.com/writing/approximation-vs-computation
  4. [4] Compliance-Owned Copy vs. Model-Cited Answers. https://worthune.com/writing/compliance-copy-vs-model-cited