Glazecalc MCP server

• Registry namecom.glazecalcapp/glazecalcverified in the MCP registry

The registry name sits under glazecalcapp.com. The registry only lets a publisher use that namespace after proving control of the domain through DNS or HTTP.

• Stateanswerschecked 2026-10-28
• Tools33
• Server calls itselfglazecalc
• Server version1.3.0
• Protocol version2025-06-18

On 2026-10-28 the server answered initialize and tools/list without a sign-in. First answer in 131 ms.

• Its tools do every use case we checked: calculate a glaze recipe's unity molecular formula; compare two glaze recipes by their fluxes and silica ratio; find a replacement for a discontinued glaze material.

Said by rules from the measurements above. The likely first call is a model's pick from the tool list; read its description before relying on it.

• INITE MCP score68 of 100answers 100 · does the job 100 · definitions 95 · context 58 · use 0 · connects 100 · lowered by the warning signs below
• What an agent can do with it3 of 3 use cases
• Answered100% of days7 of 7 daily checks
• Median first answer113 ms
• Space in an agent's context≈ 14,040 tokensthe definitions of all its tools (33), which an agent carries on every turn
• Tool definitionsA · 95 of 100
• Typed results0 of 33 toolsdeclared outputSchema: results come typed, read once

• Parameters without a description: in 10 of 33

A program checks the server once a day: initialize and tools/list, no model. Tokens are the definitions' length at about four characters a token. The grade averages six checks of every tool's name, description, schema and annotations; it says how well the tools are described, not whether they work. The score weighs what was measured and nothing else: answering (25%), doing the product's job (25%), definitions (20%), context (10%), use (10%) and how readily a client connects (10%). A part that was not measured is left out, and a hidden instruction caps the score at 40. The state of vendors' MCP servers: method and numbers →

• search_materials

  Finds ceramic raw materials (feldspars, clays, frits, fluxes) and, if asked, colorants in Glazecalc's library by name, alias or maker. Use it to find the exact name the other tools take.

• get_material

  One material from Glazecalc's library: its oxides, loss on ignition, whether it is discontinued and what replaces it, where it is sold, hazards and the data sheet it comes from.

• analyze_recipe

  Works out a glaze recipe's unity (Seger) formula, oxide groups, silica to alumina ratio, fired analysis, loss on ignition and calculated thermal expansion, as the Glazecalc app does. stull says where the recipe sits on Stull's chart…

• check_limits

  Checks a glaze recipe for what is past a recommended limit for its firing (too much boron or alkali, too little alumina, too little or too much clay, rising expansion...) and says what the fired glaze will likely do, as the Glazecalc app…

• convert_cone_temperature

  Converts between a pyrometric cone and its temperature, and between °C and °F. Orton cones run 022 to 42: Glazecalc's figure, from 022 to 15, is Orton's older chart for large cones at 150 °C an hour, and Orton's current figures…

• suggest_substitutes

  Finds the discontinued or scarce materials in a recipe and the modern ones that replace them, then suggests amounts that keep the unity formula as near as the materials allow, as the Glazecalc app does. report.closeness says how near the…

• match_from_materials

  Remakes a glaze recipe from only the materials listed in "have", keeping its unity formula as near as they allow, as Match with what I have does in the Glazecalc app. report.closeness says how near the new unity formula comes to the old…

• solve_target

  Makes a glaze recipe, in percent, from the materials given whose unity formula comes as near a target as they allow (Solve for a target in the Glazecalc app). The target is a unity formula (moles; the fluxes are scaled to add up to 1) or…

• blend_recipes

  Works out the test tiles of a line blend between recipes a and b (2 to 11 steps), or of a triaxial blend when c is given too (2 to 6 rows, up to 21 tiles), as the Blends page of the Glazecalc app does. Each tile is a mix of the corner…

• vary_material

  Shows what one material does to a glaze, by putting more and more of it into a base recipe (an ingredient blend or progression test: whiting 0 to 20, say, in 2 to 11 tiles). With mode "add" (the default) it goes on top of the base, so the…

• compare_recipes

  Compares two glaze recipes side by side: for each, its recipe in percent, key unity formula figures, silica to alumina, calculated expansion, place on Stull's chart (stull), the names of the limit cautions it has and, with a firing…

• search_guides

  Searches Glazecalc's plain-language guides for potters (glazing from first principles, making a glaze, safe mixing, safety at home with children and pets, firing a kiln, and a companion to John Britt's free glaze course, in English only)…

• list_recipes

  Lists the glaze recipes saved in your Glazecalc account, newest first, optionally only those whose title or a material matches a search, or whose stated firing includes a cone or names an atmosphere or process ("which of my glazes fire at…

• get_recipe

  One recipe from your account: its materials and amounts, colorants, notes, its stated firing (firedAt: the cone scale, the low and optional high cone of the claimed range, the cones actually tested, the atmospheres and processes, and for…

• list_my_materials

  Lists the materials you have saved in your own Glazecalc account (not the shared library), with their oxides.

• get_shelf

  The materials you marked as on hand in Glazecalc (the shelf that Match with what I have uses).

• match_with_what_i_have

  Remakes one of your recipes, or a recipe you give, from only the materials on your shelf, keeping its unity formula as near as they allow (Match with what I have). report.closeness says how near the new unity formula comes to the old…

• list_firings

  Lists the firing logs saved in your Glazecalc account, newest first.

• get_firing

  One firing log from your account: its columns (time, temperature, cone...) and rows, and its notes.

• list_notes

  The notes in your Glazecalc notebook, newest first, optionally only those about one record (a recipe, material or firing log id).

• get_my_settings

  Your Glazecalc settings that matter when talking about glazes: region, temperature scale, cones, language, weight unit, whether lead may be suggested, the limit set recipes are checked against, the currency your prices are in (never the…

• create_recipe

  Saves a new glaze recipe in your Glazecalc account, from its base materials and amounts (the library's names, or your own materials'), with optional colorants, notes, firing band and food-surface mark. Glazecalc works out its unity…

• update_recipe

  Changes one of your saved recipes (an id from list_recipes): its title, its base materials and amounts (the unity formula is worked out again), its notes, firing band or food-surface mark. Only what is given changes. The recipe as it was…

• add_notebook_entry

  Adds an entry to your Glazecalc notebook (the Notebook page), with an optional title: a test result, an observation, a firing to try. With about, it is a note about one of your recipes, materials or firing logs, which list_notes finds by…

• add_my_material

  Saves a material of your own in your Glazecalc account (the Materials page) from its oxide analysis in weight percent, as on a data sheet, with its loss on ignition. Recipes can then use it by name. Needs an access token that can read and…

• update_my_material

  Changes one of your own materials (an id from list_my_materials): its name, oxide analysis in weight percent, loss on ignition or notes. Only what is given changes. Recipes already saved keep their own copy of it. The material as it was…

• add_to_shelf

  Marks materials as on hand (the shelf that Match with what I have uses), by the library's names or your own materials'. The shelf as it was is kept: undo_shelf_change puts it back. Needs an access token that can read and change your…

• remove_from_shelf

  Takes materials off the shelf of materials on hand, by name. The materials themselves stay. The shelf as it was is kept: undo_shelf_change puts it back. Needs an access token that can read and change your records.

• undo_shelf_change

  Puts back the shelf as it was before its last change (by the website, an access token or an assistant). One step back only: a second call finds nothing to undo until the shelf changes again. Needs an access token that can read and change…

• move_to_trash

  Moves one of your recipes, materials, notebook entries or firing logs to the Trash, as removing it on the website does. It can be put back from the Trash on the website for 30 days; nothing is deleted for good. A token moves at most 100…

• create_firing_log

  Saves a new firing log in your Glazecalc account (the Firing page): its title, the day, the kiln, the columns kept (time, temperature, cone, atmosphere, comments...) and a row for each reading, as the person dictated them. Add later…

• add_firing_rows

  Adds rows to the end of one of your firing logs (an id from list_firings), in the log's own columns (get_firing gives them): the readings dictated during a firing. The rows already there stay as they are, and the log as it was is kept as…

• link_firing

  Links one of your recipes to a firing log it went through, as the recipe page does, and sets what came of it there: the result in the person's words (at most 500 characters), and the cone and atmosphere when they differ from the log…