Glazecalc
REMOTE · GLAZECALCAPP.COM
Ceramic glaze chemistry: unity formulas, limit checks, substitutes, cones and potters' guides.
Available components
Last scanned (4 hours ago)
Scores higher than 61% of remote servers
Reachable. Last reached 5 Nov 2026.
Category Health and Science
Recent critical change
Authorization (22 Oct 2026). See the changelog before you install this server.
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →
Endpoint Security63
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation check failed: no authorisation is required to call this server, and it exposes a tool marked destructive (update_recipe). See how to fix → View diagnostics → Fail
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability73
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 9013 tokens (~219/item across 41 items; 33 tools + 8 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management57
- Stability observed for 17 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage96
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 88% of tool parameters carry a description.Partial
- Structured output schemas are declared (6% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- All 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.Pass
- An AI judge read all 35 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (2026-07-28).Pass
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 5 Nov 26 +1
- “add_firing_rows” added an optional parameter “rev” cosmetic
- “move_to_trash” added an optional parameter “rev” cosmetic
- “update_my_material” added an optional parameter “rev” cosmetic
- “update_recipe” added an optional parameter “rev” cosmetic
4 cosmetic changes on this day. Switch on “Show cosmetic changes” to see them.
- 4 Nov 26 0
- Tool “compare_recipes” rewrote its description, which is the text the model reads security
- Tool “vary_material” rewrote its description, which is the text the model reads security
- Tool “compare_recipes” now declares an output schema ▲ functional
- Tool “vary_material” now declares an output schema ▲ functional
- First check of Tool coverage: 6 functional
- New prompt “teach_me” functional
- Server version: 1.3.0 → 1.4.0 functional
- “compare_recipes” added an optional parameter “aRecipeId” cosmetic
- “compare_recipes” added an optional parameter “bRecipeId” cosmetic
- “compare_recipes” reworded the description of “a” cosmetic
- “compare_recipes” reworded the description of “b” cosmetic
- “compare_recipes” made “a” optional cosmetic
- “compare_recipes” made “b” optional cosmetic
- 2 Nov 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 43 to 47. That category is still filling its 30-day observation window: 13 days of observed history at the previous scan, 14 at this one. The score rises as the window fills, whether or not the server changes.
- 31 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 37 to 40. That category is still filling its 30-day observation window: 11 days of observed history at the previous scan, 12 at this one. The score rises as the window fills, whether or not the server changes.
- 29 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 30 to 33. That category is still filling its 30-day observation window: 9 days of observed history at the previous scan, 10 at this one. The score rises as the window fills, whether or not the server changes.
- 27 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.
- 25 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.
- 23 Oct 26 +1
- The server rewrote its instructions, which are the text every model session reads security
- New tool “add_firing_rows”, which the server declares destructive security
- New tool “link_firing”, which the server declares destructive security
- Tool “add_notebook_entry” rewrote its description, which is the text the model reads security
- Tool “analyze_recipe” rewrote its description, which is the text the model reads security
- Tool “blend_recipes” rewrote its description, which is the text the model reads security
- Tool “check_limits” rewrote its description, which is the text the model reads security
- Schema quality: 186 → 208 ▼ functional
- New prompt “dictation” functional
- New prompt “what_does_this_material_do” functional
- New resource “dictation-skill” functional
- Server version: 1.2.0 → 1.3.0 functional
- New tool “compare_recipes” functional
- New tool “create_firing_log” functional
- New tool “vary_material” functional
- “add_notebook_entry” added an optional parameter “about” cosmetic
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 5 Nov 2026 · Probed https://glazecalcapp.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=glazecalcapp.com | CN=YE1,O=Let's Encrypt,C=US | 15 Oct 2026 | 13 Jan 2027 | ECDSA 256 | ECDSA-SHA384 | 6b1c6a9d68055eed306a5ed81fa8aac6e05 |
| SANs: glazecalcapp.com, staging.glazecalcapp.com, www.glazecalcapp.com | ||||||
| CN=YE1,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 5ddd70dd31f801c85c186a7a04b80afe |
| CN=Root YE,O=ISRG,C=US (CA) | CN=ISRG Root X2,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | ECDSA-SHA384 | 872165fc34b6e5fba8add5b3705fb53a |
| CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | SHA256-RSA | 6c8f1dc727c7117f7baf853ac980f9cd |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of glazecalcapp.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| glazecalcapp.com. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=31536000 |
| content-security-policy | connect-src 'self'; img-src 'self' data:; font-src 'self'; style-src 'self'; frame-src 'self'; worker-src 'self'; manifest-src 'self'; form-action 'self'; frame-ancestors 'none' |
| x-content-type-options | nosniff |
| x-frame-options | DENY |
| referrer-policy | strict-origin-when-cross-origin |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://glazecalcapp.com/mcp | Verified | 200 | |
| http (plaintext) | http://glazecalcapp.com/mcp | HTTPS enforced | 301 | https://glazecalcapp.com/mcp |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
add_firing_rows Add readings to one of my firing logs ~208
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 an earlier version. At most 500 rows a log. Save only what the person said and agreed to; never fill in an amount, temperature or analysis they did not give. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | The firing log, from list_firings. |
| rev | integer | – | The log’s rev as you last read it. When given, the rows are added only if the log has not changed since; otherwise nothing is changed. Left out, they are always added. |
| rows | array | yes | The new readings, in the log’s own columns (get_firing gives them), each row a cell for each column. |
No output schema declared.
No examples provided.
add_my_material Add one of my materials ~193
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 change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| analysis | object | yes | Its oxides in weight percent, as on a data sheet: { "SiO2": 68.5, "Al2O3": 17.4, "K2O": 9.8 }. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| loi | number | – | Its loss on ignition in percent. |
| name | string | yes | – |
| notes | string | – | – |
No output schema declared.
No examples provided.
add_notebook_entry Add to my notebook ~127
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 that record's id. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| about | object | – | The saved record the entry is about, when it is about one: list_notes with its id finds it again. |
| content | string | yes | The entry. |
| title | string | – | – |
No output schema declared.
No examples provided.
add_to_shelf Add to the materials I have on hand ~76
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 records.
| Name | Type | Req | Description |
|---|---|---|---|
| materials | array | yes | The materials, by name. |
No output schema declared.
No examples provided.
analyze_recipe Unity formula of a recipe ~189
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 (1912, as the recipe page draws it): silica and alumina in moles, the region (unfused, matte, semi-matte, bright or underfired) and whether it falls in the crazed area; a guide to the surface, not a promise.
| Name | Type | Req | Description |
|---|---|---|---|
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| lines | array | yes | The recipe's base materials (not colorants), at most 40 lines. |
No output schema declared.
No examples provided.
blend_recipes Blend recipes for test tiles ~485
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 recipes, each taken as a percent of its base: its shares, its recipe in percent, its key unity formula figures (silica, alumina, boron, the fluxes), silica to alumina, calculated expansion, its place on the Stull chart (stull), the names of the limit cautions it has, and, with a firing, whether its chemistry fits that firing (coneFit verdict). With two recipes and steps 2 it compares them oxide by oxide (differences). Give base materials only, no colorants. This is a calculation from published figures, not a test result: the tiles, fired, decide, and the cautions are guides, not a guarantee of food safety.
| Name | Type | Req | Description |
|---|---|---|---|
| a | array | yes | Recipe A, the first corner (the line's first tile, or the top of the triangle). |
| b | array | yes | Recipe B (the line's last tile, or the triangle's bottom left). |
| c | array | – | Recipe C, the triangle's bottom right. Leave it out for a line blend between a and b. |
| firing | object | – | The firing, as a cone or a temperature. Leave it out when it is not known. From cone 12 up (about 1320 °C) no published glaze limits reach, so the limits are not checked there; the cone check judges… |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| limitSet | string | – | The limits to check against, as check_limits takes it: "glazecalc" (the default) or "hesselberth-roy". |
| steps | integer | – | Tiles in the line (2 to 11, default 5), or rows of the triangle when c is given (2 to 6, default 4). |
No output schema declared.
No examples provided.
check_limits Check a recipe against limits ~538
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 does. A cone is checked in the band the recipe page gives it (low cone 06-02, mid 1-7, high 8-11); from cone 12 up (band 'top') no published limits reach, so the band's limits are not checked and limitsNote says so. With a firing, coneFit says whether the chemistry looks like that firing's, by Katz's boron rule and Hesselberth & Roy's silica and alumina whatever limit set is chosen: verdict 'cooler' or 'hotter' only when boron and silica or alumina agree on another band; 'fits' (nothing points away, not a pass); 'skipped' where the published figures do not reach (lead, lithium, much soda and potash or zinc, raku, cones 01 to 3, cooler than cone 06 or hotter than cone 10...). Cone 6 against cone 10 is told apart only roughly (strength 'soft'). stull says where the recipe sits on Stull's chart, as analyze_recipe gives it. These are cautions and guides from published figures, not a test and not a guarantee of food safety.
| Name | Type | Req | Description |
|---|---|---|---|
| firing | object | – | The firing, as a cone or a temperature. Leave it out when it is not known. From cone 12 up (about 1320 °C) no published glaze limits reach, so the limits are not checked there; the cone check judges… |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| limitSet | string | – | The limits to check against: "glazecalc" or "hesselberth-roy" (Hesselberth & Roy, cone 6 and 10 only, no low-fire figures). Neither has figures from cone 12 up. Left out: the limit set saved in the a… |
| lines | array | yes | The recipe's base materials (not colorants), at most 40 lines. |
No output schema declared.
No examples provided.
compare_recipes Compare two recipes ~578
Compares two glaze recipes side by side: for each, its recipe in percent, key unity formula figures, flux ratio (R2O against RO), silica to alumina, calculated expansion, place on Stull's chart (stull), the names of the limit cautions it has and, with a firing, whether its chemistry fits that firing (coneFit verdict); then what changes from A to B oxide by oxide (differences), which materials are in A only, in B only, or in both, with their percents, and a summary of the differences that matter (flux ratio, silica to alumina, silica, alumina and boron, expansion with fitFlag when the two differ by 0.3 x10^-6 per °C or more, so they may fit the same clay differently, Stull regions, the cautions only one side has, and coneFit). Give each recipe as lines (a, b) or, signed in to Glazecalc, one of your own saved recipes by its id from list_recipes (aRecipeId, bRecipeId): one or the other for each side. It is the same comparison blend_recipes makes with two recipes and two steps, under a name that is easy to find. Give base materials only, no colorants. This is a calculation from published figures, not a test result: fire both, and the tiles decide.
| Name | Type | Req | Description |
|---|---|---|---|
| a | array | – | Recipe A as lines (or give aRecipeId instead). |
| aRecipeId | string | – | Recipe A as one of your own saved recipes, by its id from list_recipes (signed in only), instead of a. |
| b | array | – | Recipe B as lines (or give bRecipeId instead). |
| bRecipeId | string | – | Recipe B as one of your own saved recipes, by its id from list_recipes (signed in only), instead of b. |
| firing | object | – | The firing, as a cone or a temperature. Leave it out when it is not known. From cone 12 up (about 1320 °C) no published glaze limits reach, so the limits are not checked there; the cone check judges… |
| labels | array | – | Names for A and B, two of them, such as ["Original", "With whiting"], echoed back. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| limitSet | string | – | The limits to check against, as check_limits takes it: "glazecalc" (the default) or "hesselberth-roy". |
| Name | Type | Req | Description |
|---|---|---|---|
| a | object | yes | – |
| b | object | yes | – |
| celsius | number | – | – |
| differences | array | yes | – |
| limitBand | string|null | – | – |
| limitSet | string | – | – |
| limitsNote | string | – | – |
| materials | object | yes | – |
| note | string | yes | – |
| summary | object | yes | – |
No examples provided.
convert_cone_temperature Cones and temperatures ~202
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 (self-supporting cones at 15, 60 and 150 °C an hour, large cones at 60 and 150, cone 022 to 14) come beside it; Orton publishes no figure above cone 14, so cones from 16 up have none. SK cones (JIS R 8101, SK 022 to SK 20) by the standard's nominal figures. Give a cone, or a temperature to find the nearest cones.
| Name | Type | Req | Description |
|---|---|---|---|
| celsius | number | – | – |
| chart | string | – | – |
| cone | string | – | – |
| fahrenheit | number | – | – |
No output schema declared.
No examples provided.
create_firing_log Save a new firing log ~291
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 readings with add_firing_rows. Save only what the person said and agreed to; never fill in an amount, temperature or analysis they did not give. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| columns | array | yes | The columns kept, by these names, as on the Firing page: Time, Temperature F or Temperature C (the scale said), Cone, Atmosphere, Ramp, Hold, Damper, Comments and the rest. |
| date | string | – | The day it was fired, as 2026-10-21; today when left out. |
| kiln | string | – | The kiln, as the person names it. |
| notes | string | – | Anything else said about the firing, in the person’s words. |
| rows | array | yes | One row for each reading, one cell for each column, in column order, as the person said it ("9:40", "1850", "5 bending"); "" for a cell not said. |
| title | string | yes | The log’s name, as the person gave it ("Glaze firing, cone 6"). |
No output schema declared.
No examples provided.
create_recipe Save a new recipe ~305
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 formula, as the recipe page does, and answers with it. Save only a recipe the person asked to save. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| colorants | array | – | Colorants and opacifiers added to the base, as the recipe page lists them; left out of the unity formula. |
| firing | string | – | The firing band its limits are checked in: low (cone 06-02), mid (cone 4-6), high (cone 9-11) or top (cone 12 up, where no limit set has figures, so none are checked), as the recipe page chooses it. |
| foodSurface | boolean | – | Whether it is meant for a food surface (a liner). |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| lines | array | yes | The recipe's base materials (not colorants), at most 40 lines. |
| notes | string | – | Notes kept with the recipe. |
| title | string | yes | The recipe’s name. |
No output schema declared.
No examples provided.
get_firing Get one of my firing logs ~44
One firing log from your account: its columns (time, temperature, cone...) and rows, and its notes.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | The id from a list. |
No output schema declared.
No examples provided.
get_material Get a material ~60
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.
| Name | Type | Req | Description |
|---|---|---|---|
| name | string | yes | Its name or alias. |
No output schema declared.
No examples provided.
get_my_settings My settings ~91
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 prices), and whether changes made by assistants wait for your approval on the website (confirmChanges: off, removals or all; it can be changed only there).
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
get_recipe Get one of my recipes ~515
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 a temperature the rate and hold; each cone exactly as the potter gave it), whether it is for a food surface, the firing logs it went through with a result note each and, where known, the cone and atmosphere each was fired at, the potter’s summary of how it came out at each cone and atmosphere (coneResults; one outside the stated firing is kept), the firing band and target specific gravity saved with it, and its unity formula worked out afresh. It is checked against the limit set chosen in your settings: for the firing given here, or else the band chosen on the recipe, or else the bands its stated firing falls in (a range across two bands is checked at each). A firing from cone 12 up is band 'top', where no limit set has figures: its limits are not checked, and limitsNote says so. coneFit says, for the same firing, whether the chemistry looks like that firing's, as the recipe page's limits panel does: by Katz's boron rule and Hesselberth & Roy's silica and alumina whatever limit set is chosen, a note (verdict 'cooler' or 'hotter') only when boron and silica or alumina agree on another band, 'closer' when a range across bands looks nearer one end, 'fits' when nothing points away (not a pass), 'skipped' where the published figures do not reach (among them firings cooler than cone 06 or hotter than cone 10). Cone 6 against cone 10 is told apart only roughly (strength 'soft'). A guide, not a test.
| Name | Type | Req | Description |
|---|---|---|---|
| firing | object | – | The firing, as a cone or a temperature. Leave it out when it is not known. From cone 12 up (about 1320 °C) no published glaze limits reach, so the limits are not checked there; the cone check judges… |
| id | string | yes | The id from a list. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
No output schema declared.
No examples provided.
get_shelf Materials I have on hand ~32
The materials you marked as on hand in Glazecalc (the shelf that Match with what I have uses).
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
link_firing Save a test result for a recipe in a firing ~271
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. Linked already, it changes only what is given. A recipe links to at most 100 logs. Taking a link off is done on the website. Save only what the person said and agreed to; never fill in an amount, temperature or analysis they did not give. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| atmosphere | string | – | oxidation, reduction or neutral, when the person says it. |
| cone | string | – | The cone it was fired to there, as the recipe page writes it ("6", "06", "5.5", SK "6a", or "1240" for °C), when it differs from what the log says. |
| firingId | string | yes | The firing log it went through, from list_firings. |
| recipeId | string | yes | The recipe, from list_recipes. |
| result | string | – | What came of it in that firing, in the person’s words (at most 500 characters; put longer text in a notebook entry about the recipe). |
No output schema declared.
No examples provided.
list_firings List my firing logs ~65
Lists the firing logs saved in your Glazecalc account, newest first.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | How many to return, 25 by default. |
| offset | integer | – | How many to skip, for the next page. |
| search | string | – | – |
No output schema declared.
No examples provided.
list_my_materials List my materials ~74
Lists the materials you have saved in your own Glazecalc account (not the shared library), with their oxides.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | How many to return, 25 by default. |
| offset | integer | – | How many to skip, for the next page. |
| search | string | – | – |
No output schema declared.
No examples provided.
list_notes List my notebook ~90
The notes in your Glazecalc notebook, newest first, optionally only those about one record (a recipe, material or firing log id).
| Name | Type | Req | Description |
|---|---|---|---|
| about | string | – | Only the notes about this record id. |
| limit | integer | – | How many to return, 25 by default. |
| offset | integer | – | How many to skip, for the next page. |
| search | string | – | – |
No output schema declared.
No examples provided.
list_recipes List my recipes ~320
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 cone 10 reduction?"). Each lists its stated firing; a recipe with none has not stated one.
| Name | Type | Req | Description |
|---|---|---|---|
| atmosphere | string | – | Only recipes stated for this atmosphere. |
| cone | string | – | Only recipes whose stated firing includes this cone ("6", "06", "5.5", SK "6a"), or for scale "temperature" this °C. A range matches any cone inside it; recipes tested at it come first. Recipes state… |
| limit | integer | – | How many to return, 25 by default. |
| offset | integer | – | How many to skip, for the next page. |
| process | string | – | Only recipes stated for this firing process. |
| scale | string | – | The scale the cone is in: Orton (the default), SK (JIS R 8101) or a temperature in °C. |
| search | string | – | – |
No output schema declared.
No examples provided.
match_from_materials Remake a recipe from given materials ~312
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, oxide by oxide: close (within 0.02, or 5% of a large amount such as silica's), off, or far (more than three times that), with a verdict (close, fair or poor) and a summary. report.miss and report.best are the solver's own scores, for comparing runs. Raw clay is held to 20% of the batch where that costs the match little (report.capped and allowMore say more). Test any suggestion before using it.
| Name | Type | Req | Description |
|---|---|---|---|
| allowMore | array | – | Materials whose suggested cap to lift, as report.capped names them: raw clay is held to 20% of the batch (or the recipe's own share) where that costs the match little. |
| have | array | yes | The library names of the materials on hand. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| lines | array | yes | The recipe's base materials (not colorants), at most 40 lines. |
| mustUse | array | – | Materials on hand that must stay in. |
No output schema declared.
No examples provided.
match_with_what_i_have Remake a recipe from what I have ~208
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, oxide by oxide, as match_from_materials does. Test any suggestion before using it.
| Name | Type | Req | Description |
|---|---|---|---|
| allowMore | array | – | Materials whose suggested cap to lift, as report.capped names them: raw clay is held to 20% of the batch (or the recipe's own share) where that costs the match little. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| lines | array | – | Or a recipe given line by line. |
| recipeId | string | – | One of your recipes, from list_recipes. |
No output schema declared.
No examples provided.
move_to_trash Move one of my records to the Trash ~186
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 an hour, and none while the Trash is full. Remove only what the person asked to remove. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | Its id, from list_recipes, list_my_materials, list_notes or list_firings. |
| kind | string | yes | What it is: a note is a notebook entry. |
| rev | integer | – | The record’s rev as you last read it. When given, the change is made only if the record has not changed since; otherwise nothing is changed. Left out, the change is always made. |
No output schema declared.
No examples provided.
remove_from_shelf Remove from the materials I have on hand ~68
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.
| Name | Type | Req | Description |
|---|---|---|---|
| materials | array | yes | The materials, by name. |
No output schema declared.
No examples provided.
search_guides Search the guides ~273
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) in the language asked for, or in English where that language has no match. Returns each matching section's title, anchor, a short excerpt, its address on the website and its resource URI, which resources/read returns in full. Use it for glaze defects, safety, firing and terms, and cite the address.
| Name | Type | Req | Description |
|---|---|---|---|
| cones | string | – | How the potter fires, for the parts of the guides that differ: Orton cones (the default), SK cones (JIS R 8101) or by temperature. |
| guide | string | – | Only this guide. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| limit | integer | – | At most this many sections (5 unless asked). |
| query | string | yes | Words to look for, such as "crawling", "respirator", "bisque schedule" or "specific gravity". |
No output schema declared.
No examples provided.
search_materials Search the material library ~168
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.
| Name | Type | Req | Description |
|---|---|---|---|
| category | string | – | Only this category: feldspar, clay, frit, flux, silica... |
| includeColorants | boolean | – | Also search colorants and opacifiers. |
| limit | integer | – | – |
| query | string | yes | Words in the name, such as "custer", "ferro 3134" or "kaolin". |
| region | string | – | Where the potter buys materials, so suggestions are ones sold there: US, UK, EU or AU. Leave it out for any. |
No output schema declared.
No examples provided.
solve_target Make a recipe for a target formula ~467
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 an oxide analysis (percent by weight of the fired glaze), with potash and soda apart. Give the materials by their library names, or onHand for the materials on the person’s shelf (with a token or connected app that may read it). closeness says how near each oxide comes: close (within 0.02, or 5% of a large amount such as silica’s), off, or far (more than three times that), with a verdict (close, fair or poor) and a summary; unreachable names the target’s oxides nothing given supplies. Raw clay is held to 20% of the batch where that costs the match little (capped and allowMore say more). Test any recipe before using it.
| Name | Type | Req | Description |
|---|---|---|---|
| allowMore | array | – | Materials whose suggested cap to lift, as report.capped names them: raw clay is held to 20% of the batch (or the recipe's own share) where that costs the match little. |
| firing | object | – | The firing, as a cone or a temperature. Leave it out when it is not known. From cone 12 up (about 1320 °C) no published glaze limits reach, so the limits are not checked there; the cone check judges… |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| materials | array | – | The library names of the materials to make it from. Use search_materials to find the names. |
| mustUse | array | – | Materials given that must be in the recipe. |
| onHand | boolean | – | Make it from the materials on the person’s shelf, as well as any named: needs a token or connected app that may read it. |
| target | object | yes | The unity formula or oxide analysis to aim for. |
No output schema declared.
No examples provided.
suggest_substitutes Substitutes for old materials ~254
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 new unity formula comes to the old, oxide by oxide, as match_from_materials does. Test any suggestion before using it.
| Name | Type | Req | Description |
|---|---|---|---|
| allowLead | boolean | – | Whether materials with lead may be suggested. Off by default. |
| allowMore | array | – | Materials whose suggested cap to lift, as report.capped names them: raw clay is held to 20% of the batch (or the recipe's own share) where that costs the match little. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| lines | array | yes | The recipe's base materials (not colorants), at most 40 lines. |
| region | string | – | Where the potter buys materials, so suggestions are ones sold there: US, UK, EU or AU. Leave it out for any. |
No output schema declared.
No examples provided.
undo_shelf_change Undo the last change to the materials I have on hand ~64
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 your records.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
update_my_material Change one of my materials ~271
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 is kept as an earlier version, so the person can undo the change on the website. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| analysis | object | – | Its oxides in weight percent, as on a data sheet: { "SiO2": 68.5, "Al2O3": 17.4, "K2O": 9.8 }. |
| id | string | yes | The material, from list_my_materials. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| loi | number | – | – |
| name | string | – | – |
| notes | string | – | – |
| rev | integer | – | The record’s rev as you last read it. When given, the change is made only if the record has not changed since; otherwise nothing is changed. Left out, the change is always made. |
No output schema declared.
No examples provided.
update_recipe Change one of my recipes ~316
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 is kept as an earlier version, so the person can undo the change on the website. Needs an access token that can read and change your records.
| Name | Type | Req | Description |
|---|---|---|---|
| firing | string | – | The firing band its limits are checked in: low (cone 06-02), mid (cone 4-6), high (cone 9-11) or top (cone 12 up, where no limit set has figures, so none are checked), as the recipe page chooses it. |
| foodSurface | boolean | – | – |
| id | string | yes | The recipe, from list_recipes. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| lines | array | – | All of its base materials, in place of the ones it has. |
| notes | string | – | Its notes, in place of the ones it has. |
| rev | integer | – | The record’s rev as you last read it. When given, the change is made only if the record has not changed since; otherwise nothing is changed. Left out, the change is always made. |
| title | string | – | – |
No output schema declared.
No examples provided.
vary_material What one material does across a range ~659
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 recipe grows; with mode "replace" the same amount comes out of another material of the base (`instead`), so the total stays the same. Each tile has its amount of the material, its recipe in percent, its key unity formula figures (silica, alumina, boron, the fluxes), silica to alumina, calculated expansion, its place on Stull's chart (stull: region, crazed), the names of the limit cautions it has, and, with a firing, whether its chemistry fits that firing (coneFit verdict), and its flux ratio (fluxRatio: R2O alkalis against RO fluxes, in the unity formula). trend sums up what moves from the first tile to the last (oxides, silica to alumina, expansion, the R2O share of the flux ratio), which Stull regions the tiles cross, the first tile with a limit caution the first tile does not have (firstCaution) and, with a firing, the first whose coneFit verdict changes (firstConeFitChange). Give base materials only, no colorants. This is a calculation from published figures, not a test result: the tiles, fired, decide, and the cautions are guides, not a guarantee of food safety.
| Name | Type | Req | Description |
|---|---|---|---|
| firing | object | – | The firing, as a cone or a temperature. Leave it out when it is not known. From cone 12 up (about 1320 °C) no published glaze limits reach, so the limits are not checked there; the cone check judges… |
| from | number | – | The least of it, in the unit the recipe lines share (default 0: the base alone). |
| instead | string | – | With mode "replace": the material of the base that gives way to it. |
| language | string | – | The language for any sentences in the answer, as a BCP 47 tag such as "en", "de" or "ja". Languages Glazecalc does not offer are answered in English. |
| limitSet | string | – | The limits to check against, as check_limits takes it: "glazecalc" (the default) or "hesselberth-roy". |
| material | string | yes | The material to vary, by its library name (search_materials finds it), such as "Whiting". |
| mode | string | – | "add" (the default): put the material on top of the base. "replace": take the same amount out of `instead`, so the total stays the same. |
| recipe | array | yes | The base recipe the material goes into. |
| steps | integer | – | Tiles from from to to (2 to 11, default 5). |
| to | number | yes | The most of it, in the unit the recipe lines share: it must be more than from. |
| Name | Type | Req | Description |
|---|---|---|---|
| baseTotal | number | yes | – |
| celsius | number | – | – |
| from | number | yes | – |
| instead | string | – | – |
| limitBand | string|null | – | – |
| limitSet | string | – | – |
| limitsNote | string | – | – |
| material | string | yes | – |
| mode | string | yes | – |
| note | string | yes | – |
| steps | integer | yes | – |
| tiles | array | yes | – |
| to | number | yes | – |
| trend | object | – | – |
No examples provided.
How do I install the Glazecalc MCP server?
Glazecalc is a hosted endpoint at https://glazecalcapp.com/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
remote · glazecalcapp.com
claude mcp add --transport http com-glazecalcapp-glazecalc 'https://glazecalcapp.com/mcp'
What is the Glazecalc MCP server?
Glazecalc is an MCP server listed in the public MCP registry as com.glazecalcapp/glazecalc. Ceramic glaze chemistry: unity formulas, limit checks, substitutes, cones and potters' guides. This page covers its hosted endpoint (https://glazecalcapp.com/mcp).
Is the Glazecalc MCP server safe to use?
Glazecalc scores 74 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the Glazecalc MCP server expose?
Glazecalc exposes 33 tools: search_materials, get_material, analyze_recipe, check_limits, convert_cone_temperature, and 28 more. Their descriptions and schemas cost roughly 8,000 tokens of context every time the server is loaded.
Does the Glazecalc MCP server require authentication?
No. We connected to Glazecalc without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Glazecalc MCP server still maintained?
Glazecalc is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.