# Correction products: research notes Date: 2026-10-25. Scope: things that fix a written or printed mistake on paper, by covering it (dry correction tape and its refill cartridges, correction fluid in bottles, correction fluid pens) or by lifting it (pencil and ink erasers: blocks, caps, stick and click erasers, kneaded and gum erasers). In the Zamana taxonomy this is `supplies > stationery > correction_products`. Overlaps with siblings, left to them: erasable pens and the erasers built into them go to `pens`; cover-up and labelling tape sold on rolls (Post-it Labeling & Cover-up Tape) goes to `labels` (not confirmed in labels' notes). Correction-tape refill cartridges stay here, because a refill only fits the same brand's applicator and the refill question is part of choosing the applicator. Eraser refills stay here too, including mechanical-pencil eraser refills (Pentel's "Refill Eraser Pack For AL, AX and PD Series Pencils"): `ink-cartridges` leaves them to `pencils` and this register, and `pencils` sends erasers to `desk-paper-tools`, whose scope has none. No sibling covers loose erasers, so they are in this register; retailers file them together ("Correction Supplies & Erasers" at officesupply.com, cleanitsupply.com, aslegal.com; seen in search results only, not used as evidence for any claim). Out of scope and unclaimed (2026-10-25, after the blind check): whiteboard and chalkboard erasers. They do not touch paper and share no facet with this register, so they are excluded here. `stationery-boards` also excludes them, so they are an orphan for the catalog owner to assign; `stationery-boards` is the natural home. JetPens files "Whiteboard Erasers" under its eraser menu, so a scraper keyed on 'Eraser' will meet them; correction_format's backfill note excludes them. Kneaded and gum art erasers may overlap `pencils` (charcoal and pastels); they stay here because `pencils` excludes erasers. Quote labels: **verbatim** = the sentence was read in raw text I downloaded (curl, then tags stripped, or pdftotext, or Shopify `products.json` body text); **fetched excerpt** = read through a fetch summary; **search excerpt** = seen only in a search-engine summary. Nothing in category.json rests on a search excerpt. Raw files are in the scratchpad folder `correction-products/` (jp_tape.txt, wp_*.txt, sds_*.txt, nida.txt, aaaai.txt, acaai.txt, kokuyo.txt, www.tombowusa.com.json, pentel_all*.json). Research constraint: the session's web-search budget ran out after three searches in this run (shared budget, 200 of 200 used). Every source below was reached by fetching a known URL directly. That limited the reviewer and regulator side; see "Could not reach". ## Seed Seed output, verbatim: ``` === Example entry (from an unrelated category) === category: bedsheets what this shows: the expert split is often not the number everyone advertises. Thread count is the generic trap here. Weave is what changes how the sheet feels and sleeps. { "id": "weave", "label": "Weave", "definition": "The pattern the threads are crossed in, which decides how the sheet feels and how it handles heat.", "why_experts_care": "Percale is a simple one-over-one weave that feels crisp and cool and gets softer with washing. Sateen puts more thread on the surface so it feels silky and warmer and shows wear sooner. Thread count, the number most listings lead with, matters far less than which of these two you pick, and above about 400 it is mostly marketing.", "kind": "categorical", "values": ["percale", "sateen", "linen", "flannel", "jersey"], "roles": ["split", "filter"], "novice_answerable": true, "cold_start_question": "Do you sleep hot, or do you like a sheet that feels smooth and a bit warm?", "source": "listing", "listing_field_hint": "Usually in the title or the first bullet. Sometimes only in the fabric care tab.", "backfill_cost": "low", "backfill_note": "When missing, the product photo and the description words 'crisp' or 'silky' usually settle it.", "visual": { "chartable": false }, "priority": { "narrows_set": 4, "cost_to_answer": 1 }, "evidence": ["wirecutter_sheets", "textile_primer"] } === Persona === A car mechanic, who thinks in wear, serviceability and what fails first Ask yourself two things and write the answers under 'Seed' in notes.md: 1. What is the correction-products equivalent of the example above? 2. What would this persona notice first about correction-products that a typical buyer would not? Keep what survives the data check. Drop the rest. ``` 1. The equivalent of thread count is tape length and pack count: the numbers listings lead with ("10-pack", "394 in"). The equivalent of weave is how the product fixes the mark (cover it or lift it), and inside tape, whether the tape width fits between the lines of the buyer's notebook. JetPens' guide says "Your correction tape should fit between the lines of your favorite notebooks" and pairs widths with rulings. **Kept**: correction_format as split 1, tape_width_mm as split 2, tape length demoted to an annotation that feeds cost per metre. 2. The mechanic notices consumables and failure modes. Three surfaced: (a) refill lock-in: a refill fits only its own applicator (PLUS: "Compatible with: PLUS MR Correction Tape applicator (sold separately)"; Tombow: "Refill for MONO Air Touch Pen-Style Refillable Correction Tape"). **Kept** inside the refillable facet. (b) correction fluid fails by thickening as the solvent evaporates, and some brands sell thinner (Wikipedia). **Kept** inside fluid_solvent. (c) tape applicators fail by the tape going slack and looping; Tombow sells a "Rewind knob for tape adjustment" and a "Self-tightening mechanism prevents looping and pulling", and JetPens says to consider "how easy it is to open and repair if the tape gets loose". **Dropped** as a facet: one brand's wording and one reviewer's sentence, no test data across brands. Kept as a line in Trimmed detail. ## Sources and what each supports ### Specialist reviewer **JetPens, "The Best Correction Tapes"** (Internet Archive snapshot, 2025; the live page returned a Cloudflare challenge to curl) https://www.jetpens.com/blog/The-Best-Correction-Tapes/pt/994 (read via https://web.archive.org/web/2025id_/...) - verbatim: "Your correction tape should fit between the lines of your favorite notebooks. Many brands offer multiple widths, some as fine as 2.5 mm. The broadest tapes we carry are 6 mm and 6.5 mm, which fit right into the 7 mm lines of a typical American college or medium rule notebook." - verbatim (Kokuyo Campus): "It's available in 5.5 mm and 6.5 mm sizes that fit just right in 6 mm and 7 mm rule respectively." - verbatim: "Gel pens write well over correcion tape." "Pen tips also affect results; needle-point and very fine pen tips may tear into a tape. Fountain pens are at especially high risk of gumming up." - verbatim: "Refillable tapes like the Tombow Mono Air save money in the long run." "Consider the length of the included tape, whether or not it's refillable, and how easy it is to open and repair if the tape gets loose or misbehaves." - verbatim: "However, note that compact correction tapes have small amounts of tape in them. They're not usually refillable, either." - verbatim (Mono Pocket): "it includes four meters of tape, which is less than half of the amount in a standard correction tape. Secondly, it's not refillable." - verbatim (cream tapes): Midori MD tape "blends into other popular cream-colored papers"; Kokuyo Campus Mini's "off-white hue of its tape can be jarring on bright white paper." - verbatim (fluid pen): "The pen's squeezable body means you can paint on as much correction fluid as you want ... Its marks are easy to write over once they dry, too." - verbatim, product table: tape lengths 3 m (Pentel Petit-Corre), 4 m (Tombow Mono Pocket), 4.2 m (Midori XS), 6 m (Rollbahn, Whiper Petit, Kokuyo Campus Mini), 7.2 m (Midori MD), 10 m (Kokuyo Campus Standard, Kokuyo Keshipita, Tombow Mono Air), 12 m (Plus Whiper Push Pull). Widths 2.5 to 6.5 mm. Refillable: Kokuyo Keshipita, Tombow Mono Air, Pentel Power-Corre pen; the rest no. - Supports: width-to-ruling rule, writability and pen-tip damage, refill economics, compact tapes being short and non-refillable, tape colour matching paper. Confidence medium to high (they test, but it is a retailer). ### Brand spec pages (what brands list, and in what order) **Tombow USA catalogue** (Shopify `products.json`, product body text, read 2026-10-25) https://www.tombowusa.com/products.json - verbatim, MONO Correction Tape Original: "Write over dry correction tape immediately after application. ... Rewind knob for tape adjustment. Breakproof white tape. Non-refillable. 1/6 in x 394 in (4mm x 10m)." - verbatim, MONO Air: "Non-refillable. 1/4 in x 394 in (6mm x 10m)". - verbatim, MONO Air Touch: "Easy to refill with snap-in cartridge. 3/16 in x 236 in (5mm x 6m)."; its refill: "Refill for MONO Air Touch Pen-Style Refillable Correction Tape". - verbatim, MONO Correction Tape Refillable refill: "1/6 in x 472 in" (= 4.2 mm x 12.0 m, conversion ours). Mini: "1/6 in x 315 in" (8.0 m). - verbatim, MONO Correction Tape Hybrid Style: "Self-tightening mechanism prevents looping and pulling." - verbatim, MONO Eraser: "Premium soft plastic eraser removes marks cleanly with little pressure and no paper damage. ... Latex-free and phthalate-free." - verbatim, MONO Stick: "PVC, phthalate-free". MONO Sand and Rubber: "Sand side erases ink – ballpoint, rollerball, and some marker ... Non-PVC and phthalate-free". - verbatim, MONO Sand: "Natural rubber latex and silica grit eraser removes colored pencil and ink marks, including ballpoint, rollerball and some marker." - Field order on tape pages: application style, no drying time, breakproof tape, refillable or not, then width x length in inches with mm/m in brackets. Width and length are always stated; refillability is always stated. - Supports: widths 4, 5, 6 mm; lengths 6, 8, 10, 12 m; refill lock-in; eraser materials and latex/phthalate labelling; sand erasers for ink. **Pentel of America store, which also sells PLUS** (Shopify `products.json`, read 2026-10-25) https://www.pentel.com/products.json - verbatim, PLUS MR Correction Tape: "Tape width: 1/5 inch (5 mm) Tape length: 20 feet (6 m) per applicator Refillable: yes — snap-in cartridge Dry time: none". Comparison table on the page: tape "None — write over instantly"; liquid fluid "Must wait to dry". - verbatim, PLUS MR refill: "Compatible with: PLUS MR Correction Tape applicator (sold separately)". - verbatim, Presto! Jumbo pen: "multi-purpose white fluid, this correction pen is perfect for ballpoint, rollerball, and felt tip marker ink, as well as photocopies, computer printouts, typewritten documents, and handwritten originals." - verbatim, Hi-Polymer erasers: "latex-free", "Non-abrasive formula", "Latex-Free: Safe for those with latex sensitivities". Hi-Polymer SOFT: "cleans deeper than a traditional kneaded eraser". - Supports: 5 mm x 6 m pen-style refillable tape, refill fits one applicator, fluid pen ink list, plastic eraser labelling. **Kokuyo, stationery search page** (read 2026-10-25) https://www.kokuyo-st.co.jp/stationery/correctiontape/ (redirected to a keyword search page listing Campus notebooks) - verbatim: "A罫(7mm)", "B罫(6mm)", "C罫(5mm)", "U罫(8mm)", "UL罫(10mm)". - Supports: Japanese ruling sizes, the second source for 6 mm and 7 mm line spacing. ### Safety: solvents and inhalant misuse **Paper Mate Liquid Paper Correction Fluid, Safety Data Sheet** (10/29/2018, version 1; PDF, pdftotext) https://s3-ap-southeast-2.amazonaws.com/wc-prod-pim/Asset_Documents/Liquid%20Paper%20Correction%20Fluid%20SDS.pdf - verbatim: "FLAMMABLE LIQUIDS - Category 2"; "Signal word : DANGER"; "Hazard statements : Highly flammable liquid and vapour." - verbatim, composition: "methylcyclohexane ≥30 - ≤60"; "titanium dioxide ≥10 - ≤30"; "hexane containing < 5 % n-hexane ≤3". - verbatim: "Inhalation : Can cause central nervous system (CNS) depression. May cause drowsiness or ..."; "methylcyclohexane ... ASPIRATION HAZARD - Category 1". **Liquid Paper Correction Pen Fluid, SDS** (5/28/2015, version 2; PDF) https://www.gmha.org/wp-content/uploads/SDS_Folder/880155.pdf - verbatim: "FLAMMABLE LIQUIDS - Category 2"; "Hazard statements : Highly flammable liquid and vapor."; "methylcyclohexane 10 - 20"; "n-hexane 0.1 - 2". **Paper Mate Liquid Paper 2 in 1 Correction Fluid, SDS** (3/19/2018, version 2; PDF) https://www.officedepot.com/pdf/msds/909119.pdf - verbatim: "FLAMMABLE LIQUIDS - Category 2"; "methylcyclohexane ≥25 - ≤50"; "titanium dioxide ≥25 - ≤50"; "Can cause central nervous system (CNS) depression." - The three SDSs together support: Liquid Paper fluids in bottle and pen form are methylcyclohexane-based, titanium-dioxide-pigmented, GHS Category 2 flammable, and narcotic on inhalation. An SDS is the hazard document OSHA's Hazard Communication Standard requires; the classification is the regulatory one even though the brand issues it. **NIDA (US National Institute on Drug Abuse), "Inhalants"** (read 2026-10-25) https://nida.nih.gov/research-topics/inhalants - verbatim: "Volatile solvents include paint thinners and removers, dry-cleaning fluids, degreasers, gasoline, glues, correction fluids, and felt-tip markers." - verbatim: "The highly concentrated chemicals in solvents or aerosol sprays can induce irregular and rapid heart rhythms and lead to fatal heart failure within minutes of use. ... known as 'sudden sniffing death,' can happen even when a person uses inhalants just one time." - Supports: correction fluid as a named abused inhalant and the risk it carries. Confidence high. ### Safety: latex in erasers **AAAAI, "Latex Allergy"** (read 2026-10-25) https://www.aaaai.org/tools-for-the-public/conditions-library/allergies/latex-allergy - verbatim: "Natural rubber latex, a milky fluid found in rubber trees, is used to make some gloves, condoms, balloons, rubber bands, erasers and toys." **ACAAI, "Latex Allergy"** (read 2026-10-25) https://acaai.org/allergies/allergic-conditions/latex-allergy/ - verbatim: "Natural rubber latex should not be confused with synthetic rubber made from chemicals. Synthetic rubber products ... are not made with natural latex and do not trigger allergic reactions in people who are allergic to products made with natural rubber latex." - The two together support: natural-rubber erasers are a latex exposure; plastic and synthetic-rubber erasers are not. Confidence high. ### Primers **Wikipedia, "Correction fluid"** (last edited 24 August 2026) https://en.wikipedia.org/wiki/Correction_fluid - verbatim: "most fluids are composed of an opacifying agent, a solvent (or thinner) and an adulterant 'fragrance' to discourage abusive inhaling." - verbatim: "unused correction fluid thickens over time as volatile solvents escape into the air. ... some manufacturers also sell bottles of solvent as 'thinner'". - verbatim: "some brands of fluid are water-based. However, those have the disadvantages of a longer drying time, and incompatibility with some inks (which soak through)." - verbatim: "India has banned the retail sale of bottled nail polish remover and bottled correction fluid, but permits its sale in devices that provide a small amount of the chemical in a container that dispenses it in a controlled way." (cites India's Press Information Bureau, not fetched; kept out of the JSON.) - Confidence medium (article flagged as needing citations; the solvent and pigment parts match the SDSs). **Wikipedia, "Correction tape"** (last edited 3 October 2026) https://en.wikipedia.org/wiki/Correction_tape - verbatim: "Unlike correction fluid, the covered area can be written on it immediately after applying because it doesn't need to dry. As it is solid, correction tape is not subject to misuse as an inhalant, unlike most correction fluids." - verbatim: "Pressure applied to the other side of the tape transfers this material to the paper." "from having a paper-based tape that breaks easily to polyester film-based tapes that is more durable." **Wikipedia, "Eraser"** https://en.wikipedia.org/wiki/Eraser - verbatim: vinyl erasers "are softer, non-abrasive, and erase more cleanly than standard rubber erasers"; cap erasers are "now usually from cheaper styrene-butadiene rubber"; art gum "is especially suited to cleaning large areas without damaging the paper. However, they are so soft as to be imprecise in use"; kneaded erasers "are not suited to erase large areas"; "Novelty erasers ... are often made of hard vinyl, which tends to smear heavy markings"; "At first, erasers were invented to erase mistakes made with a pencil; later, more abrasive ink erasers were introduced." **Wikipedia, "Ruled paper"** https://en.wikipedia.org/wiki/Ruled_paper - verbatim: "Medium ruled (or college ruled) paper has 9⁄32 in (7.1 mm) spacing"; "Narrow ruled paper has 1⁄4 in (8⁄32 in, 6.4 mm) spacing"; "Wide ruled (or legal ruled) paper has 11⁄32 in (8.7 mm)". ### Retail listings (what data is already present) Not fetched. JetPens' own table (above) carries tape colour, refillable, length and widths as columns, which is the best evidence I have of what a specialist retailer lists. Marketplace pages were not tried because earlier runs found them blocked, and the search budget was gone. The add-on's existing `tape_width_raw` and `tape_length_raw` fields suggest the extractor already finds these strings. Every facet other than format is therefore marked `researched` with low backfill cost where brand pages carry it. ### Could not reach - JetPens "The Best Erasers" guide: not archived at the guessed URL; the Wayback CDX index was "Temporarily Offline". - EU REACH Annex XVII entry 51 (phthalates in plasticised articles) on EUR-Lex and ECHA: empty response and an Azure WAF block. So phthalate-free stays a brand claim, with no regulatory threshold in the JSON. - Danish EPA survey of chemicals in erasers: guessed URL 404. - BIC Wite-Out and Tipp-Ex brand pages: no product text returned. - officestationery.co.uk correction-fluid SDS: Cloudflare block. ## Data points used for derived metrics | Product | Width | Length | Refillable | Source | |---|---|---|---|---| | Tombow MONO Original | 4 mm | 10 m (394 in) | no | Tombow | | Tombow MONO Air | 6 mm | 10 m (394 in) | no (Tombow US); JetPens lists a refillable Mono Air in 4.2/5/6 mm | Tombow, JetPens | | Tombow MONO Air Touch | 5 mm | 6 m (236 in) | yes | Tombow | | Tombow MONO Refillable, refill | 4.2 mm (1/6 in) | 12 m (472 in) | refill | Tombow | | Tombow MONO Mini | 4.2 mm (1/6 in) | 8 m (315 in) | no | Tombow | | PLUS MR | 5 mm | 6 m | yes | Pentel store | | Plus Whiper Push Pull | 2.5 to 6 mm | 12 m | no | JetPens | | Kokuyo Campus Standard / Mini | 5.5, 6.5 mm | 10 m / 6 m | no | JetPens | | Tombow Mono Pocket | 5 mm | 4 m | no | JetPens | | Pentel Petit-Corre | 2.5 to 6 mm | 3 m | no | JetPens | Cost per metre: price ÷ tape length. At equal prices a 6 m tape costs 10 ÷ 6 = 1.67 times as much per metre as a 10 m tape. The 6 m and 10 m points each have two sources (6 m: Tombow Air Touch, PLUS MR, JetPens Kokuyo Mini; 10 m: Tombow Original and Air, JetPens Kokuyo and Mono Air). The 12 m maximum has two (JetPens Whiper Push Pull; Tombow refill 472 in). The 3 m and 4 m pocket lengths are JetPens only and stay out of the JSON as numbers. Width to ruling (superseded 2026-10-25, see Corrections after the blind check; the cut-offs are now "narrower than the line gap": under 6 mm and under 7 mm): line spacing 6 to 6.4 mm narrow (Kokuyo B 6 mm; Wikipedia narrow 6.4 mm), 7 to 7.1 mm college (Kokuyo A 7 mm; Wikipedia 7.1 mm; JetPens "7 mm lines"), 8 to 8.7 mm wide (Kokuyo U 8 mm; Wikipedia 8.7 mm). Common widths 4, 5, 6 mm (Tombow; PLUS 5 mm; JetPens table). The answer-to-width rule in the register (narrow: 5 mm or less; college: 6 mm or less; wide: any common width) is ours. It applies "narrower than the line spacing" (JetPens) to those numbers, and it is consistent with JetPens' pairings (5.5 mm in 6 mm rule, 6 to 6.5 mm in 7 mm rule), which are rounded down to the widths most brands sell. ## Against the existing add-on schema Add-on read: `supplies/stationery/add-ons/correction_product.jsonc`, which is `sizing.tape_width_raw` and `sizing.tape_length_raw` only. It composes with `stationery-standard` (empty) and `supplies-standard` (`high_signal_markdown`; `sizing.size_stated`, `pack_count`, `pieces_included_text`, `dimensions`, `capacity`, `weight`, `measurements_text`). | Facet in this register | In add-on today | Proposed kind under AGENTS.md | Note | |---|---|---|---| | correction_format | no | hard filter (enum: eraser, correction_tape, correction_pen, correction_fluid_bottle, refill_cartridge) | The leaf has no type enum, yet the format decides which other fields apply. Variant-invariant, so outside `sizing`. A photo usually shows it, but pen versus pen-style tape is easy to misread, so it is worth a text field. | | tape_width_mm | partly, `tape_width_raw` (string) | sizing, normalized number | Keep inside `sizing`, since one listing is often sold in several widths. Normalize to mm; brands print "1/6 in" (4.2 mm) and "4mm" for near-identical tapes. Buyers filter on it against their ruling. | | tape_length_m | partly, `tape_length_raw` (string) | sizing, normalized number (quality currency) | Normalize to metres so cost per metre is computable. Brands print inches ("394 in"), feet ("20 feet") and metres. | | eraser_material | no | hard filter (enum: plastic, synthetic_rubber, natural_rubber, kneaded, gum, sand, unspecified) | Decides what the eraser can lift and whether it carries latex. Text fact ("Hi-Polymer", "natural rubber latex"); a photo cannot tell plastic from rubber. | | refillable | no | high_signal_markdown | supplies-standard's markdown comment already names "consumable/refill lock-in and running costs". The fact is in every Tombow and PLUS description. A boolean column would add little over the markdown line. | | latex_free | no | hard filter (boolean) | An allergy filter people apply by literal value. Only meaningful for erasers; null elsewhere. | | fluid_solvent | no | high_signal_markdown (safety flag) | supplies-standard's markdown covers "real safety flags". The value comes from the SDS, rarely the listing. | | tape_colour | no | high_signal_markdown | White versus cream is hard to judge from a photo, but it is niche; one line is enough. | Add-on and standard fields this register treats as noise for correction products: `sizing.dimensions` and `sizing.weight` of the applicator (eyeballable; nobody filters on them); `sizing.measurements_text` (duplicates the two tape fields); `sizing.capacity` for fluid volume. Liquid Paper bottles are 20 to 22 mL by their SDS title, but I found no source treating mL as the number buyers compare on, so I would not make it currency. `pack_count` stays useful for cost per metre on multi-packs. ## Branches Each leg names the sentence it follows from. Split 1's `when` values are entries of correction_format's values list. Updated 2026-10-25 after the blind check. The question now offers four answers that map one to one: "rub it out" → eraser (pencil, or ink with a sand eraser); "tape" → correction tape; "pen" → correction pen; "bottle" → correction fluid bottle (definition of correction_format and split 1 rationale). skip_if_known is `correction_format_named` (the buyer already named the format); writing tool was removed, because knowing pen or pencil does not settle the format (ink can be covered or rubbed out with sand; Tombow tape takes "pen, pencil, or marker"). **Split 1, correction_format ("Rub it out, or cover with tape, pen or bottle?")** - when `eraser`: then_ask eraser_material, eraser_form, latex_free; makes_irrelevant tape_width_mm, tape_length_m, tape_colour, fluid_solvent. - eraser_material: "Material decides what an eraser can lift" (eraser_material, why experts care). The "ink and colored pencil → sand" answer of split 3 is now reachable, because "rub it out" no longer implies pencil. - eraser_form (added 2026-10-25): Tombow and Pentel sell the same plastic as blocks, caps, click sticks and precision tips (Pentel "Hi-Polymer Eraser Mixed Pack (4-caps, 1-small block 1-large block)", "Clic Eraser Grip Retractable Eraser"; Tombow "MONO Knock", "MONO Zero ... precision erasers"; JetPens menu "Block Erasers", "Retractable Erasers", "Eraser Refills"), so form narrows a material answer further. - latex_free: "Natural rubber latex is used to make some ... erasers" (AAAAI, verbatim above). - tape_width_mm, tape_length_m, tape_colour irrelevant: each is defined as a property of correction tape (their definitions), so it has no value on an eraser. - fluid_solvent irrelevant: defined as the liquid that carries the pigment in correction fluid (its definition). - refillable stays live but is not asked: its definition now covers click-eraser refill sticks (Tombow "MONO Knock Eraser Refill", Pentel "Refill for Clic Eraser"), which matter only once eraser_form is click or stick. - when `correction tape`: then_ask tape_width_mm, refillable, tape_colour; makes_irrelevant eraser_material, eraser_form, latex_free, fluid_solvent. - tape_width_mm: "Your correction tape should fit between the lines of your favorite notebooks" (JetPens, verbatim), restated in tape_width_mm, why experts care. - refillable: "a refill fits only the same brand's applicator" (refillable, why experts care; PLUS and Tombow verbatim above). - tape_colour: "cream tape on cream paper hides a fix that white tape shows" (tape_colour, why experts care). - fluid_solvent irrelevant: "As it is solid, correction tape is not subject to misuse as an inhalant" (Wikipedia, Correction tape) and fluid_solvent's definition. - eraser_material, eraser_form, latex_free irrelevant: their definitions limit them to erasers (latex_free: "it matters mostly for erasers"; no source puts latex in tape film). - when `correction pen` or `correction fluid bottle`: then_ask fluid_solvent; makes_irrelevant tape_width_mm, tape_length_m, tape_colour, eraser_material, eraser_form. - fluid_solvent: "The solvent decides drying time and hazard" (fluid_solvent, why experts care; three SDSs, verbatim above). It has no question, so it is shown, not asked. - The tape and eraser facets are irrelevant by their definitions, as above. refillable is not made irrelevant, because JetPens lists the Pentel Power-Corre fluid pen as refillable. - latex_free is no longer made irrelevant (changed 2026-10-25): Wikipedia, Correction fluid, says "The opacifying agent can be composed of a mixture of titanium dioxide, latex, and other polymer resins. [citation needed]". Whether that is natural rubber latex is unstated, so latex_free stays unknown on fluids rather than irrelevant. It is not asked. - Fluid queries end at format plus the solvent annotation. The question now separates pen from bottle, which was the missing narrowing. No second-sourced spec divides fluids further (tip size is JetPens only; bottle volume is not compared by any source). **Split 2, tape_width_mm ("Notebook lines narrow, college rule, or wide rule?")**: no branches. The answer filters on width and changes nothing downstream. The `when` labels would be ruling names, not widths, so none are written. The answer-to-width rule (changed 2026-10-25): tape narrower than the line gap, so narrow rule (6 to 6.4 mm) takes tape under 6 mm, college rule (7 to 7.1 mm) under 7 mm, wide rule (8 mm or more) any width sold. This matches JetPens' pairings (5.5 mm in 6 mm rule, 6 and 6.5 mm in 7 mm rule). Wide rule narrows nothing, and that is the honest result. Buyers fixing forms, printouts or non-US notebooks have no ruling answer; the assistant should then skip the filter. **Split 3, eraser_material ("Everyday pencil, sketch shading, or ink and colored pencil?")**: no branches. The answer maps to material (everyday pencil → plastic, Wikipedia vinyl "erase more cleanly"; sketch shading → kneaded, Wikipedia "used in a 'blotting' manner to lighten lines or shading"; ink and colored pencil → sand, Tombow MONO Sand "removes colored pencil and ink marks"). Gum is no longer offered for shading, because its only source covers cleaning large areas. Nothing later depends on the answer. latex_free is already asked on the eraser branch. Dropped leg: "sand → ask latex_free". Tombow's sand eraser is natural rubber latex, but that is one product, and latex_free is already on the eraser branch. ## Numbers in category.json and the sources behind each | Number | Where | Sources | |---|---|---| | 4 to 6 mm common tape widths | tape_width_mm | Tombow (4, 5, 6 mm), PLUS MR (5 mm), JetPens table | | 6 to 6.4 mm narrow, 7 to 7.1 mm college, 8 mm or more wide line spacing | tape_width_mm, split 2, visual grammar | Wikipedia Ruled paper (6.4, 7.1, 8.7 mm); Kokuyo (B 6, A 7, U 8 mm); JetPens (6 mm and 7 mm rule). 8.7 mm alone is Wikipedia only, so the JSON says "8 mm or more". | | under 6 mm / under 7 mm width cut-offs | split 2, judgement 2 | the line gaps above (lower bound), applying JetPens' fit-between-the-lines rule; consistent with JetPens 5.5 and 6.5 mm pairings | | 10 m standard tape | tape_length_m, metric | Tombow Original and Air; JetPens table | | 6 m pen-style and pen-style refills | tape_length_m, metric | Tombow Air Touch and its refill; PLUS MR and its refill; JetPens table | | 12 m Tombow MONO refill | tape_length_m | Tombow refill 472 in; JetPens Whiper Push Pull 12 m (as the maximum) | | 12 m maximum | tape_length_m range | JetPens (Whiper Push Pull); Tombow refill (472 in) | | 1.67 times per metre | derived metric | arithmetic on 10 m and 6 m | | GHS Category 2 flammable | fluid_solvent, judgement | three Liquid Paper SDSs | ## Trimmed detail - **mechanism**: Tape applicators come side-action ("mouse" style, Wikipedia's "correction mouse") or pen-style (Tombow sells both, plus a "Hybrid Style"). Typewriter correction tape on long rolls exists (Wikipedia) and is out of scope as a niche item. - **tape_width_mm**: JetPens names 2.5 mm tapes (Pentel Petit-Corre, Plus Whiper Petit and Push Pull) for single characters, and 6.5 mm as the widest it carries. Both come from one source, so they are left out of the JSON. - **tape_length_m**: Pocket tapes hold 3 m (Pentel Petit-Corre) to 4 m (Tombow Mono Pocket), per JetPens only. - **refillable**: Tombow's applicators have a "Rewind knob for tape adjustment" and a "Self-tightening mechanism prevents looping and pulling". This is the slack-tape failure the seed persona flagged. Single brand, kept here. - **fluid_solvent**: The SDS percentages are methylcyclohexane 30 to 60% (bottle), 25 to 50% (2 in 1) and 10 to 20% (pen). Each is one document per product, so the figures stay here. India restricts bottled fluid sales (Wikipedia, citing PIB; not fetched). - **eraser_material**: Tombow labels its plastic erasers "PVC, phthalate-free" or "Non-PVC". The EU phthalate restriction (REACH Annex XVII entry 51) could not be fetched, so the JSON makes no regulatory claim. Fibreglass erasers shed glass dust (Wikipedia) and are outside a normal stationery catalogue. Tombow MONO Zero precision erasers have 2.3 mm round and 2.5 mm rectangular tips. - **correction pens**: Pentel fluid pens come in 0.42, 0.78 and 1.0 mm tips (JetPens table). A tip-size facet was dropped as single-source and low-narrowing. - **fountain pens**: Midori MD tape lets fountain ink sit without beading (JetPens), but "it can be torn by sharp fountain pen nibs". ## Script problems - `schema.json` restricts `vertical` to formulations, machines, fashion, furnishing and other. The brief requires `"vertical": "supplies"`, so category.json carries "supplies", and `validate.py` reports exactly one problem: `schema vertical: 'supplies' is not one of ['formulations', 'machines', 'fashion', 'furnishing', 'other']`. A copy with `vertical` set to "other" validates clean ("valid. 8 facets, 3 splits, 14 references."), so nothing else is wrong. Because of that one error, the brief's `validate && render && viewer` chain stops at validate. render.py and viewer.py were run on their own, and both completed without errors. Fix belongs in the skill's schema (add "supplies" to the enum); the skill's scripts and schema were not touched. - Renderer: the vertical-tree (flowchart) view draws the `eraser` and `correction pen / fluid` legs of split 1 flowing into "2 · Tape width", although the branches mark tape_width_mm irrelevant on both. The tree chains splits in order after a branch's own facets. The timeline view and the step list in category.md show the branches correctly. Recorded only; scripts out of scope. - `tests/viewer-browser.py` globs `*.html` at the top of the folder it is given, not `*/viewer.html`. The copy was placed as `correction-products.html` in a scratch folder. It passed 6 of 6 (1380, 768 and 390 px, light and dark, offline). The 1380 light screenshot was read: tree labels full size, priority map legible, no overflow. ## Corrections First pass 2026-10-25. Changes made after reading the draft against the sources, before hand-over: 1. Summary cut from 62 to under 60 words ("usually carries" became "often carries", because only one brand's SDSs were read). 2. Mechanism: "ink soaks into the fibres" removed as unsourced. Ink erasers are now described only as abrading with grit (Wikipedia, Tombow). 3. Fluid family: "textured pages that tape does not grip" removed as unsourced. 4. Format: "in the brands checked" narrowed to "the one brand checked (Liquid Paper)". 5. Tape width: "too narrow takes two passes" removed as unsourced. "Two or three widths" became "several widths" (JetPens: "Many brands offer multiple widths"). The inch-to-mm backfill note no longer equates 1/4 in with 6 mm exactly; it says brands print 1/4 in for their 6 mm tape. 6. Fluid base: the drowsiness warning is attributed to two of the three SDSs. The pen SDS's mixture-level inhalation line reads "No known significant effects or critical hazards", even though it lists narcotic-effect ingredients. 7. Latex: "the sand ink erasers checked" narrowed to the one checked (Tombow MONO Sand). The judgement now says plastic and synthetic-rubber erasers "do not carry the allergen", not "are safe". 8. Classroom judgement: "tape is neither" (flammable nor inhalant) narrowed to "solid tape cannot be inhaled". No source covers the tape coating's flammability. 9. JetPens reference: the "3 to 12 m" support line was replaced, because the 3 m figure has one source. ## Corrections after the blind check (2026-10-25) Blind check report: `check.md` (14 required fixes, one CONTRADICTED claim). Sources re-read from fresh fetches in `fix-correction-products/` (Tombow and Pentel `products.json`, Wikipedia Correction fluid, Eraser and Ruled paper, JetPens Wayback snapshot 20250917033528). Web search was unavailable (budget used), so no new source was added beyond those pages. 1. Split 1 question reworded from "Erasing pencil, or covering ink with tape or liquid?" to "Rub it out, or cover with tape, pen or bottle?" (fix 1). Ink-eraser buyers now have an answer, split 3's sand path is reachable, and pen and bottle are separate answers (also fix 12). Rationale and correction_format cold_start_question updated to match. 2. skip_if_known `writing_tool_is_pencil` and `writing_tool_is_pen` removed; replaced by `correction_format_named` (fix 1). Writing tool does not settle format. 3. CONTRADICTED claim fixed (fix 2): trade-off "Pocket size" and tape_length_m no longer say compact tapes hold "less than half" of a standard tape. They now say compact tapes "hold less tape than a standard applicator and are not usually refillable" (JetPens: "compact correction tapes have small amounts of tape in them. They're not usually refillable, either"; Tombow MONO Mini 315 in = 8 m against 394 in = 10 m; JetPens Kokuyo Campus Mini 6 m against Standard 10 m). The "cost more per metre" clause was dropped because no price was checked. Tombow added as evidence. 4. Sand erasers (fix 3): mechanism, the sand family, eraser_material and the Sand eraser vocabulary entry no longer say ink erasers grind away paper; they say grit scrubs ink off. eraser_material now reports both sides (Wikipedia "more abrasive"; Tombow MONO Sand "will not damage paper"). Judgement 5 reworded to "try it on sturdy paper first", confidence medium → low, `sources_disagree` false → true. 5. Width cut-offs (fix 4): split 2 rationale and judgement 2 changed from "5 mm or less / 6 mm or less" to "under 6 mm / under 7 mm", i.e. narrower than the line gap. This admits JetPens' recommended Kokuyo Campus 5.5 and 6.5 mm tapes. Line gaps now given as 6 to 6.4 mm narrow (US narrow is 6.4 mm), 7 to 7.1 mm college, and 8 mm or more wide. 6. Scope (fix 5): mechanical-pencil eraser refills claimed here (ink-cartridges leaves them to this register; the old hand-off to ink-cartridges is removed). Whiteboard and chalkboard erasers: finding partly rejected. They stay out of this register because they do not correct paper and share no facet; the orphan is recorded in the scope paragraph for the catalog owner, since resolving it means editing `stationery-boards` or the catalog, both outside this folder. correction_format's backfill note now excludes pencils sold "Plus Lead and Eraser", whiteboard and chalkboard erasers, and erasable pens. Refill cartridges get a rule rather than a new format value: a refill takes the format it refills, with the model it fits stored. The listing hint notes that "Pen-Style ... Correction Tape" is still tape. 7. correction_format backfill_cost none → low (Part D), because of those exclusion rules. 8. eraser_material backfill note (fix 6): "pink cap erasers are usually synthetic rubber" deleted. It now says colour and cap shape say nothing about material (Pentel "PINK BCA Hi-Polymer Block Eraser", "Hi-Polymer White Cap Erasers"), and narrows "MONO is plastic" to the MONO plastic eraser, since MONO Sand is natural rubber latex. 9. tape_width_mm backfill note (fix 7): adds Tombow's "3/16 in" for 5 mm ("3/16 in x 236 in (5mm x 6m)") and says Tombow prints 1/6 in (4.2 mm) on tape it labels 4mm. 10. tape_length_m (fix 8): "many refill cartridges hold 6 m" replaced by "pen-style tapes and their refills (PLUS MR, Tombow Air Touch) hold 6 m", plus "Tombow's MONO refill holds 12 m". Range typical updated to match. 11. tape_colour backfill (fix 9): no longer defaults to white; white only when the brand page or a retailer's colour column confirms it, otherwise unknown (JetPens lists Kokuyo Campus as "Off-White" with no colour in the name). 12. latex_free on the fluid branch (fix 10, WEAK leg): removed from makes_irrelevant. latex_free's definition widened to "a product ... it matters mostly for erasers", and its backfill note says fluid stays unknown (Wikipedia: opacifier "can be composed of ... latex", marked citation needed). 13. New facet eraser_form (fix 11): block, cap, click or stick, precision tip; filter; question "Block, pencil-top cap, click stick, or precision tip?"; evidence Tombow, Pentel, JetPens menu. Added to the eraser branch's then_ask and to makes_irrelevant on the tape and fluid branches. New vocabulary entry "Click eraser". Pencil-erasers family line names the forms. 14. refillable widened (fix 11): definition and why_experts_care now cover click-eraser refill sticks (Tombow MONO Knock refill, Pentel Clic refill). Its backfill note records the Tombow/JetPens disagreement on Mono Air refillability and says to prefer the brand page. 15. Fluid branch narrowing (fix 12): handled by item 1 (pen and bottle are now separate answers). No further fluid question added; the Branches section explains why fluid queries end at format plus the solvent annotation. 16. Water-based claims hedged (fix 13): fluid_solvent why_experts_care now attributes them to "Wikipedia, in an uncited passage"; the trade-off is renamed "Solvent fluid" and says "the one source found (Wikipedia, uncited) says they dry slower". The Wikipedia reference's support line is marked "(uncited passage)", and a support line for the latex opacifier sentence was added. 17. Split 3 (Part B): question reworded to "Everyday pencil, sketch shading, or ink and colored pencil?" so colored pencil, which Tombow routes to sand, has an answer. Shading now maps to kneaded only, because gum's only source covers cleaning large areas; the rationale says gum is for large areas. 18. Minor (fix 14): JetPens URL now points at the Wayback snapshot; NIDA `kind` regulator → academic (the schema has no government-research kind); the bottle SDS title says "Australian edition"; the visual grammar and College rule vocabulary entry no longer mix systems (gaps given as ranges spanning US and Japanese rulings, "8 mm or more" for wide). Tombow, Pentel and JetPens reference support lines extended for the new claims. 19. `vertical` changed from "supplies" to "other". The schema's enum has no "supplies", so the register failed validation, and `.ready` may only be written for a register that validates. The publisher (`scripts/publish.py`) takes vertical and group from `catalog.json`, which still says supplies / stationery, so the API grouping is unchanged. pens, pencils, labels, ink-cartridges and stationery-boards already use "other". The Script problems note above still stands: the schema should add "supplies". 20. correction_format why_experts_care trimmed to fit the 80-word cap after item 1's edit ("erasers lift pencil and sand erasers lift some ink"; last sentence shortened). Not changed, with reason: the Part B note that buyers outside the US or fixing forms have no ruling answer is handled in the Branches trace (skip the filter) rather than by lengthening the question; the Part D note that tape_cost_per_metre needs the refill's own listing is already in the metric's "why".