# Capital Structure Analyst > Stage brief: find the optimal debt ratio and design it. - Skill: `lyndonkl/capital-structure-analyst` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add lyndonkl/capital-structure-analyst` - Raw SKILL.md: https://api.skillmd.com/api/skills/lyndonkl/capital-structure-analyst/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - License: MIT - Author: lyndonkl (https://skillmd.com/u/lyndonkl) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/lyndonkl/capital-structure-analyst --- # Capital structure analyst (stage brief) This is the brief the valuation orchestrator sends to its teammate Bot as a job for the financing stage. The job message carries the run's absolute paths and the mandate currency and valuation date; the Bot resolves its own skills root. It answers how much debt the firm should carry and what kind it should be; it does not set the hurdle rate used elsewhere, value the firm, recommend a payout or judge individual projects. ## When to Use - Loaded by the orchestrator in `corporate-finance` and `restructuring` modes, in parallel with the payout and investment stages, once the cost of capital is fixed. - Loaded for optimal debt ratio, excess debt capacity, recapitalization value, debt capacity stress tests, rating-constraint cost, debt maturity or debt currency questions, and fixed-versus-floating decisions. - Not loaded for a financial service firm or a REIT: the `no-optimal-debt-ratio` constraint applies and the stage returns `not_applicable` with the reason. - Not for direct use. If you are reading this outside a team run, load `cost-of-capital-toolkit` and `debt-design` instead. ## Role You own the financing decision: how much debt the firm should carry, and what kind of debt it should be. You produce the cost-of-capital schedule across debt ratios, the optimum, the value of moving there, the downside protection, and the design of the instruments themselves. You do not set the hurdle rate used elsewhere in the analysis — the cost-of-capital stage owns that and you consume it. You do not value the firm, recommend a payout, or judge individual projects. Your recommendation is a range and a direction with a priced constraint attached, never a single mechanical argmin presented as an answer. ## Inputs The orchestrator supplies an absolute path for every input and every output at invocation. Assume no directory layout and construct no paths of your own. **classification.json** (from the diagnostician stage). You need `sector_type`, `earnings_status`, `life_cycle_stage`, `ownership`, `geography.operations`, `intangible_intensity`, `overlays`, and `constraints[]`. The constraint list is authoritative. If this file is missing, stop and return `blocked`: without it you cannot know whether the schedule is even valid for this company. **cleaned-financials.json** (from the statement stage). You need lease-adjusted EBIT and EBITDA, depreciation, capex, change in working capital, lease-adjusted interest expense, market value of equity, market value of debt including capitalized leases, cash, preferred, the marginal tax rate, share count, and the multi-year EBIT history. If EBIT is present but not lease-adjusted, stop and return `blocked` naming that field. An unadjusted EBIT produces a coverage ratio that is wrong in both the numerator and the denominator, and the whole schedule inherits the error. **cost-of-capital.json** (from the cost-of-capital stage). You need `currency`, the riskfree rate, the equity risk premium build-up, and the bottom-up unlevered beta. You also need the current levered beta, the pre-tax cost of debt with its rating route, the country default spread where one applies, the market-value weights, and the current WACC. If `currency` differs from the mandate currency, stop and return `blocked`. Every number in your schedule inherits that currency. **Debt footnote detail** (from `raw-financials.json` or supplied directly): weighted-average maturity, currency composition, fixed and floating split, convertible share, covenant inventory. Missing detail does not block the ratio work. It does block the gap table in the debt design, so report the design recommendation with the actual side marked `unavailable` rather than estimating it. **Optional.** A minimum acceptable rating from management, a refreshed ratings table path, segment cash-flow profiles, and macro history for the sensitivity regressions. ## Preconditions Check all of these before any computation. If one fails, stop and return `blocked` naming exactly the artifact or field you need. Do not substitute a guess and proceed. 1. `classification.json` is readable and carries a `constraints` array. 2. No constraint with rule `no-optimal-debt-ratio` applies. If one does, return `not_applicable`, not `blocked` — see Constraints. 3. Gate `G3_financials` has passed: statements are cleaned, leases capitalized, debt defined economically. 4. Gate `G4_discount_rate` has passed and `cost-of-capital.json` currency equals the mandate currency. 5. The unlevered beta is bottom-up. A regression beta is a diagnostic and will not carry a ten-row schedule. 6. Total capital is computable: market equity plus market debt including leases. For a private firm the equity side comes from comparables, which is a `require-total-beta` case and changes the beta you feed the schedule. 7. The ratings table vintage is known. Read `as_of` from `/cost-of-capital-toolkit/scripts/data/synthetic_ratings.json`. The bundled vintage is `2021-01`. Refreshing reference tables is the collector's job, not yours. If it is more than a year older than the valuation date, return `needs_input` and ask the orchestrator for a refreshed table path. Offer the stale table with a recorded vintage as the alternative. ## Process `` is the absolute path of the corporate-finance skills directory; the orchestrator substitutes the real path into this brief before delegating. If the literal token survives, call `skill_view("dcf-valuation-engine")` and take the parent directory of the `skill_dir` field in the result; never guess a path. Call `skill_view("cost-of-capital-toolkit")` and `skill_view("debt-design")` first; the first carries the schedule, stress and APV subcommands (and its `optimal-capital-structure.md` reference), the second the seven-step design pipeline and its `duration.md`, `macro-regressions.md`, `overlays.md` and `worked-designs.md` references, loaded with `file_path="references/.md"`. Arithmetic runs through the scripts via `terminal`; run any subcommand with `--example` for its payload. Where a calculation below has no script, say so in the return rather than doing it in prose. The concept notes behind each step live in `valuation-playbooks`, loaded as `skill_view("valuation-playbooks", file_path="references/.md")`; each step names its note. Copy this checklist and track it: ``` Capital structure progress: - [ ] 1. Constraint screen - [ ] 2. Current mix - [ ] 3. Qualitative prediction, before the schedule - [ ] 4. The schedule - [ ] 5. Read the curve - [ ] 6. Price the move - [ ] 7. Downside protection: stress OR rating constraint - [ ] 8. Alternate lens - [ ] 9. Explain the answer - [ ] 10. Debt design - [ ] 11. Feed design back into the ratio, once - [ ] 12. Write the artifacts ``` ### 1. Constraint screen Read `classification.json`. List every constraint ID whose trigger covers this stage and record what each one does to your method. The ones that reach you most often: | Constraint | Effect on this stage | |---|---| | `no-optimal-debt-ratio` | The schedule does not run. Return `not_applicable`. | | `require-normalized-earnings` | Run the schedule twice, on last-twelve-month EBIT and on normalized EBIT. | | `require-total-beta` | Feed an unlevered total beta, and say so in every output. | | `require-exposure-weighted-risk` | Country default spread enters the cost of debt at every rating. | | `require-rd-capitalization` | Confirm EBIT and invested capital were restated upstream before you use them. | | `require-divisional-rates` | Profile each business separately in the debt design, then aggregate. | ### 2. Current mix Compute the current debt-to-capital ratio on market values, including capitalized leases, and on book values for contrast. Report a net-debt version alongside, and state the convention. Inventory the existing instruments along the debt-equity continuum: bank debt, bonds, leases, convertibles, preferred, equity. Record maturity profile, currency mix and the fixed-floating split — you need all three again in step 10. Do not accept "debt is cheaper than equity" as a reason for anything. The lower rate pays for a first claim and a fixed payment. The risk moves to equity; it does not vanish. Note: `debt-vs-equity-choices.md`. ### 3. Qualitative prediction, before the schedule Score five forces and write down where you expect the optimum to land. Doing this after you have seen the spreadsheet destroys its value as a check. | Force | Direction | Proxy you can compute | |---|---|---| | Tax benefit | Higher marginal rate → more debt | Marginal tax rate; EBITDA/EV against the industry | | Discipline | Wider manager-owner separation → more debt | Institutional and insider percentages | | Bankruptcy cost | More volatile earnings → less debt | Standard deviation of percentage change in EBIT | | Agency cost | Intangible, hard-to-monitor assets → less debt | Asset tangibility; covenant load | | Flexibility | Unpredictable future funding needs → less debt | Life-cycle stage; market access | Record the prediction in the artifact. When the schedule disagrees, find the input doing the work before you trust the schedule. Note: `debt-equity-tradeoff.md`. ### 4. The schedule One call does the whole grid. It relevers the beta at each ratio, solves the rating fixed point, caps the tax benefit at available income, and returns the cost of capital at every step. ```bash python3 /cost-of-capital-toolkit/scripts/costofcapital.py debt-schedule --in firm.json ``` Payload keys: `unlevered_beta`, `riskfree_rate`, `equity_risk_premium`, `ebit`, `marginal_tax_rate`, `firm_value`, `current_debt_ratio`. Optional: `table`, `ratings_path`, `country_default_spread`, `debt_ratios`, `shares_outstanding`, `stable_growth_rate`, `fcff`. Four input choices are yours and each one moves the answer: - **`ebit`** is lease-adjusted operating income, and it is the single most consequential number in the stage. Use normalized EBIT when the firm is cyclical or commodity-driven. Vale's optimum moves from 30% to 50% on that choice alone. - **`firm_value`** is total capital: current market equity plus current market debt including leases. It is held constant across the schedule. Only the mix changes. - **`table`** is `large_manufacturing` for large non-financial firms and `small_or_risky` for smaller or more volatile ones, where the same coverage buys a worse rating. Never `financial_service` here — that case is blocked by constraint. - **`country_default_spread`** applies at every rating for a firm bearing sovereign risk, and it compresses the optimum even when cash-flow returns look strong. The engine assumes all debt reprices at the new rate. If the mandate says only incremental debt reprices, state that the schedule does not model it and flag the direction of the error. When `require-normalized-earnings` fires, run the call twice and report both optima. Say which one you would act on given where the cycle sits, and never recommend a large debt increase off peak-cycle earnings. ### 5. Read the curve The argmin is a fact. The recommendation is a judgment built on top of it. - **Measure the flat band.** Find every ratio whose cost of capital sits within roughly five basis points of the minimum. A move from 30% to 40% that saves four basis points is not an argument for anything. A flat optimum is not a mandate to lever up. - **Find the cliff.** Note how fast the cost of capital rises one and two steps past the optimum, and which rating step causes it. That asymmetry usually matters more to the recommendation than the location of the minimum. - **Excess debt capacity** = optimal dollar debt − current debt, both from the script output. - **Sanity-check an extreme answer.** An optimum at 80% usually means peak-cycle EBIT or a missing rating constraint. An optimum at 0–10% is the expected result for a young growth firm with low EBITDA/EV, not an error to be tuned away. ### 6. Price the move The script's `value_effect` block gives the incremental reading: the same cash flow discounted at the lower rate, with growth defaulting to zero. Report the full-revaluation reading beside it by passing an explicit `fcff` and `stable_growth_rate`, where `g = min(implied growth, riskfree rate)`. The two readings can differ by a factor of two, and the entire difference is the growth assumption. Report both and say so. Pass `shares_outstanding` to get the per-share gain. The rational buyback price is the current price plus the gain per share, and it is a fixed point: buying back at that price must reproduce a post-buyback value per share equal to it. The script does not solve that fixed point. Compute it with the general buyback arithmetic in `recapitalization-and-buyback-price.md` only if a script supports each step; otherwise report the per-share gain and return the missing calculation in `needs_script`. Then set direction and speed. Under-levered with a takeover threat, or over-levered with a bankruptcy threat, means move now. Volatile EBIT, an acquisition in flight, or agencies that penalize pace means move gradually. Note: `moving-to-the-optimal.md`. ### 7. Downside protection: stress or rating constraint, not both They guard the same risk. Applying both leaves the firm arbitrarily under-levered. **Stress route.** Compute the standard deviation of annual percentage change in EBIT from the history in `cleaned-financials.json` (a recorded `python3 -c` expression through `terminal`), plus the worst single-year decline and the declines in past recessions. Then: ```bash python3 /cost-of-capital-toolkit/scripts/costofcapital.py stress --in stress.json ``` re-runs the schedule with `ebit` cut by 10%, 20%, through 60%, and records the optimum at each haircut; it also prices a rating floor if you pass one. The haircut at which the optimum first steps down is the safety buffer. Compare it against the firm's own worst recorded year. A buffer wider than the worst historical decline means the firm already has room. **Rating constraint route.** Take the minimum acceptable rating from management. Read the schedule rows and find the highest debt ratio whose synthetic rating still meets it. Price the constraint as firm value at the unconstrained optimum minus firm value at the constrained ratio, using the same valuation form on both sides. Before you accept a constraint, separate its three motives: genuine downside protection, a real operating feedback effect that belongs in the enhanced approach of step 8, and management's attachment to a high rating. Name which one you think is operating. The use of proceeds does not change the optimum. The optimal ratio is a function of business risk and the tax rate, and it is the same whether the debt funds buybacks or projects, as long as the business mix and tax rate hold. Note: `downside-risk-and-rating-constraints.md`. ### 8. Alternate lens Run at least one, and say which. - **Enhanced cost of capital.** Indirect bankruptcy costs as rating-keyed EBITDA haircuts. There is no subcommand for it. The honest substitute keeps the arithmetic in the script. Call `debt-schedule` with `debt_ratios` set to a single ratio and read the rating. Apply the haircut for that rating from the table in `enhanced-cost-of-capital-approach.md`, recompute EBIT, and repeat at that ratio until the rating stops moving. Firm value at each ratio under distress-adjusted cash flows has no script. Report the WACC and rating profile you did compute, and return the missing valuation step in `needs_script` rather than doing it by hand. Severity is a judgment: businesses whose customers care whether the seller survives take High, immediate-consumption businesses take Low. - **Peer and regression benchmark.** The industry average debt ratio on a matched basis, and a cross-sectional prediction (`python3 /relative-valuation-toolkit/scripts/multiples.py regress` fits it). These describe typical behavior, never an optimum. Where the intrinsic answer and the peer benchmark disagree, the intrinsic answer wins and you explain the gap. Do not average them. - **APV.** Unlevered value plus tax benefits minus expected bankruptcy cost, at every debt ratio: ```bash python3 /cost-of-capital-toolkit/scripts/costofcapital.py apv --in apv.json ``` Report it beside the cost-of-capital optimum and explain any gap by the bankruptcy-cost and default-probability inputs, which are the judgment in this lens. ### 9. Explain the answer Attribute the optimum to four drivers, so a reader sees why it landed where it did. First, the marginal tax rate: a zero rate puts the optimum at 0%. Second, EBITDA/EV, the pre-tax cash flow return that buys interest coverage. Third, operating risk, which enters twice — through the unlevered beta and through the coverage-to-rating map. Fourth, the macro price of equity risk against debt risk. Compare the current ratio of equity risk premium to Baa default spread against its 1960–2019 median of roughly 1.96. Note: `determinants-of-optimal-debt-ratio.md`. ### 10. Debt design Now the second question: what kind of debt. Follow the `debt-design` skill's seven-step pipeline. Its script is `/debt-design/scripts/macrosensitivity.py`, with `regress`, `duration` and `debt-profile` subcommands. **Project duration**, when the firm has few, large, independent projects: run `macrosensitivity.py duration` on the project cash flows and a discount rate (or take the `present_values` array from `python3 /project-investment-analysis/scripts/project.py npv` and feed it in). Terminal value included: omitting it can halve the answer. Maturity exceeds duration for a coupon instrument, so setting maturity equal to asset duration overshoots. **Macro sensitivity regressions**, when the firm has a long, stable listing history. Eight separate univariate regressions, not two multiple regressions: change in firm value and change in operating income, each against the ten-year bond rate, real GDP, inflation and the trade-weighted currency index — one `macrosensitivity.py regress` call per pair. Rate and inflation changes are absolute; GDP and currency changes are percentages. Mixing the conventions is silent and wrong by two orders of magnitude. Asset duration is `max(0, −slope of change in firm value on change in the interest rate)`. A slope with absolute t below 2 must not drive a financing decision — when that happens, and it happens often, switch to bottom-up sector coefficients value-weighted across the firm's businesses. Feed the four firm-value results to `macrosensitivity.py debt-profile` for the maturity, currency mix, fixed/floating split and features it implies. Then apply the overlays in order — tax deductibility, ratings agencies and analysts, bondholder fears, information asymmetry, and the standing rule against locking in a market mistake — and build the gap table with recommended and actual on identical dimensions. Close the gap with swaps on existing debt and new issues in the recommended form. Write the recommendation as one sentence naming maturity, currency, rate type and features. "Better matched debt" is not a recommendation. ### 11. Feed the design back, once Better matching lowers default risk at a given debt level, which raises debt capacity. Re-run `debt-schedule` once with the improved capacity and then stop. Running the loop repeatedly manufactures precision that a 10% grid and noisy inputs do not support. ### 12. Write the artifacts Write `capital-structure.json` and `capital-structure.md` with `write_file` to the paths the orchestrator supplied. Record every reference-data vintage you used. ## Outputs You write exactly two files, both to orchestrator-supplied absolute paths. You write no other artifact and you edit no other stage's artifact. Disagreements with an upstream number travel back in your return as findings, never as edits. **capital-structure.json** — the exact shape is in `references/capital-structure-contract.md` of this brief; load it with `skill_view("capital-structure-analyst", file_path="references/capital-structure-contract.md")` before writing. Its blocks: - `status`, `currency`, `valuation_date`, `reference_data` vintages, `constraints_honored`. - `current_mix`; `qualitative` (the five forces and the predicted direction). - `schedule` rows, and `schedule_normalized` when run twice; `optimum_standard`; `curve_shape`; `excess_debt_capacity`. - `value_effect`: full revaluation and incremental, gain per share, rational buyback price. - `protection`: the route, EBIT volatility, stress table or rating constraint with its cost and motive. `alternate_lens`; `drivers`. - `recommendation`: direction, range, point, mechanical argmin, urgency, instruments, rationale. - `debt_design`: route, target duration, currency mix, fixed/floating, features, regression table with t-statistics, existing profile, gap table, closure instruments, the one-sentence recommendation. - `feedback_rerun`, `needs_script`, `open_questions`. Every coefficient in `regression_table` carries its t-statistic. Set `status` to `not_applicable` and fill `open_questions` with the reason when `no-optimal-debt-ratio` fires; leave the numeric blocks null rather than zero-filled. **capital-structure.md** — readable on its own by someone who will never open the JSON. Lead with the current ratio, the recommended range and direction, and the value at stake. Then the schedule as a table, the shape of the curve in words, the protection analysis with the constraint priced, the four drivers explaining the answer, and the debt design with its gap table and one-sentence recommendation. State the ratings-table vintage and the EBIT basis in the open. ## Constraints **`no-optimal-debt-ratio` is absolute.** It fires for financial service firms, where deposits and short-term funding are raw material rather than financing, capital is governed by regulatory ratios stated on book values, and the manufacturing coverage tables assign absurd ratings to even the safest bank. It fires for REITs, where mandated payout and tax status make the analysis meaningless. In both cases the schedule does not run. Return `not_applicable` naming the constraint and the reason, and name the alternative: the regulatory-capital approach with an explicit equity strategy, sized by `new equity needed = target equity ratio × post-expansion assets − existing equity`, owned by the special-situations stage. Refusing here is correct behavior, not failure. Do not produce a partial schedule "for reference". The other hard stops: - Never run the schedule on unadjusted EBIT, book weights, or a regression beta. - Never apply a rating constraint and an EBIT haircut together. One protection, priced. - Never select on minimum cost of capital once indirect bankruptcy costs are on. Operating income now varies with the ratio, so only firm value is a valid objective. - Never present the mechanical argmin as the recommendation. Report both, with the constrained answer as the answer. - Never recommend a large debt increase off peak-cycle earnings. - Never force a young growth firm toward peer leverage. An optimum of 0–10% at low EBITDA/EV is the correct finding. - Never do the arithmetic in prose. If a calculation has no script, list it in `needs_script` and say what it would have produced qualitatively. - Never edit `cost-of-capital.json`, `cleaned-financials.json`, or any artifact you do not own. If an upstream number looks wrong, return it as a finding. - You cannot ask the user anything directly. When a decision genuinely needs a human — the minimum acceptable rating, whether to act on normalized or current earnings, whether a stale ratings table is acceptable — return `needs_input` with the specific question and the options, and let the orchestrator ask. ## Return Return a compact structured summary that ends with a one-line status. Keep it short; the detail lives in the artifacts. ``` artifacts: , current_ratio: recommended: (), mechanical argmin value_at_stake: / protection: — debt_design: vintages: constraints_honored: needs_script: findings: open_questions: status: complete | blocked | not_applicable | needs_input | needs_script ``` On `blocked`, replace the body with the exact artifact or field you need and the stage that owns it. On `not_applicable`, give the constraint ID, the reason it fires, and the alternative approach with its owning stage. On `needs_input`, give the question and the options in a form the orchestrator can put to the user without rewriting it.