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chemdraw-mcp

CI Release License: Apache-2.0 PyPI GitHub stars

chemdraw-mcp is an MCP server that lets Claude draw chemistry: structures, reaction schemes, textbook mechanisms, spectra, TLC plates and pH curves, rendered locally with RDKit and matplotlib as PNG and SVG files. Each drawing also opens an interactive panel in the chat — hover a functional group, switch to the PubChem data sheet, rotate a 3D model, export or add an Anki card. It is free and open source (Apache-2.0) and needs no API key, no sign-up and no ChemDraw licence.

Without

With chemdraw-mcp

Claude describes a structure in words or writes SMILES you paste elsewhere

the structure appears in the chat, as files ready for a report

figures drawn by hand in ChemDraw or ChemSketch

one sentence per figure, one style across the whole report

molar mass, CAS number and hazards from three websites

one data sheet from PubChem, or one value as text

a pH worked out with an approximation you cannot check

the exact value with the textbook approximation beside it

Quick start

  1. Download the Claude Desktop extension (chemdraw-mcp-<version>.mcpb), double-click it and confirm in Claude Desktop.

  2. Open a new chat and say "Use the ChemDraw MCP: draw caffeine".

  3. Try a prompt from the tool table below.

Other ways in (PyPI, cloning the repository, editing the config by hand) are under Installation.

Related MCP server: ChemMCP

Tools

The default profile registers 16 tools in five areas. Each description says which neighbouring tool to use instead, so the model can tell a drawing from a lookup from a calculation. Files go to ~/ChemDraw-Output/.

Area

Tool

Example prompt

Panel

Draw

generate_molecule

"Draw caffeine"

yes

batch_generate

"Draw aspirin, caffeine and paracetamol, each as its own file"

yes

compare_molecules

"What is the difference between ibuprofen and naproxen?"

yes

generate_reaction

"Draw the esterification of acetic acid with ethanol as a reaction equation"

yes

generate_mechanism

"Show me the SN2 mechanism step by step"

yes

generate_3d

"Show methane as a rotatable 3D model"

yes

Lab graphics

generate_spectrum

"Draw the IR spectrum of aspirin"

yes

generate_tlc

"TLC of my esterification: educt at Rf 0.3, product at 0.65, co-spot shows both"

yes

generate_titration_curve

"Which indicator fits the titration of phosphoric acid with NaOH? Show me the curve."

yes

generate_species_distribution

"Draw the species distribution of phosphoric acid over the whole pH range"

yes

Look up

lookup

"What is the CAS number of paracetamol?"

text

lookup_molecule_data

"Give me a data sheet for ibuprofen"

yes

predict_spectrum

"Which IR bands should aspirin show?"

text

Calculate

calculate_ph

"What is the pH of 0.1 M acetic acid, pKa 4.76?"

text

Anki

export_anki_deck

"I have an exam on NSAIDs on Friday and need to know the structures"

—

The 16th tool, save_png, is the server half of the panel's export button. It runs when you click that button and is never called by the model on its own.

Draw

Structures. generate_molecule takes a name (English, IUPAC, many German trivial names) or SMILES. Names resolve through OPSIN, PubChem and NCI; a pinned identity test checks 24 inputs against their InChIKey, and family names such as "xylene" return an isomer picker instead of a silent guess. The panel shows properties, functional groups and the Lipinski rule of five, with buttons for the data sheet, PNG export and an Anki card. Fischer and Haworth projections and all-H drawings are a view option.

Comparisons. compare_molecules draws two to four structures side by side, keeps the shared scaffold neutral and highlights what differs:

Reaction schemes. generate_reaction draws reactants, products and conditions above and below a forward (→), equilibrium (⇌) or retrosynthetic (⇒) arrow; formula digits are subscripted (H2SO4 → H₂SO₄):

Mechanisms — a textbook gallery, not a mechanism engine. generate_mechanism shows three fixed examples: SN1 (2-bromopropane + water), SN2 (bromomethane + hydroxide) and Fischer esterification (acetic acid + methanol), with curved electron-flow arrows and Next / Back through the intermediates. Substrates you name are checked for compatibility with the mechanism; they are not drawn into it. Other mechanisms are not available.

3D. generate_3d embeds one conformer (ETKDGv3, then MMFF or UFF), opens a ball-and-stick panel you drag to rotate and writes an SDF file:

Lab graphics

These tools draw the numbers they are given — peak positions, Rf values, pKa values. For a named compound the model supplies typical literature values; check them before they go into a report.

Spectra. generate_spectrum draws IR, NIR, Raman, UV/Vis, fluorescence, ORD, CD, ¹H/¹³C NMR and mass spectra with the axis conventions of each type (inverted wavenumber axis for IR, ppm from right to left for NMR, bars for MS):

TLC plates. generate_tlc draws start line, solvent front, one labelled lane per application point, the Rf value at every spot, and the mobile phase and detection as a caption:

pH curves. generate_titration_curve computes pH against titrant volume from the exact charge balance and marks equivalence points, the buffer points at half-equivalence and an optional indicator band. generate_species_distribution plots the fraction of each protonation species across pH 0–14:

Look up

  • lookup answers one question as text, picked by topic: properties (formula, mass, CAS, InChIKey), safety (GHS statements, pictograms, signal word), physical (melting and boiling point, solubility, density), biochem (ChEBI classification, UniProt entries) or pathway (KEGG pathways).

  • lookup_molecule_data builds the PubChem + GHS data sheet in the panel. The molecule panel's Data button calls it too, so a drawn structure is one click away from its data sheet (second half of the demo at the top).

  • predict_spectrum lists the IR bands a structure should show (intensity, band shape), what a measured wavenumber could belong to, and how many ¹H signals to expect with their integral ratio. It is rule-based: no chemical shifts in ppm, and diastereotopic protons count as one signal.

Lookups need an internet connection. A missing value is not evidence that a property or hazard is absent.

Calculate

calculate_ph covers weak and strong acids and bases, buffers (ratio and capacity), buffer recipes down to weighable masses, and the ionised fraction of a drug at a given pH. It solves the same exact charge balance that draws the titration curve and prints the textbook approximation beside it; where the two disagree, the answer says the approximation's assumptions no longer hold. 10⁻⁸ M HCl comes out at pH 6.98, not 8. You supply the pKa values.

Anki

export_anki_deck writes a ready-to-import .apkg with rendered structures: structure ↔ name drills (optionally both directions), cloze cards, identity reactions and spectrum band assignments, with tags and Parent::Child subdecks. Re-exporting a deck updates its cards instead of duplicating them. With the AnkiConnect add-on the cards go straight into the running Anki. curated_deck_id picks a small bundled starter deck instead of your own cards. The molecule panel's Add to Anki button adds a single structure card.

Options on the drawing tools

  • formats — ["png","svg"] by default; add "cdxml" for ChemDraw on generate_molecule, generate_reaction and batch_generate. Figures that are not structures (spectra, TLC plates) reject CDXML with an error.

  • abbreviate_groups=True — draws common substituents as Ph, Bn, OMe, OAc, tBu, CO₂H, Boc, Ts, TBS.

  • render_style — "compact" for small figures in a two-column layout, "presentation" for slides, "grayscale" for black-and-white printing. Empty means the default look.

  • annotate_stereo=True — prints CIP descriptors (R/S, E/Z) on the drawing (generate_molecule, batch_generate).

Profiles

Profile

Tools

Contents

mvp (default)

16, 12 with a panel

the five areas above

full

23, 16 with a panel

adds a substrate-scope figure, a calibration curve, pharmacology curves and three more calculators

The full profile adds:

  • generate_scope_table — the substrate-scope figure of the methodology literature: general equation with conditions on top, products below with identifier, yield and optional ee/dr.

  • generate_calibration_curve — least-squares line through your standards, unknowns read back off it, LOD/LOQ (DIN 32645); a sample outside the calibrated range is labelled as extrapolated.

  • generate_pk_curve and generate_dose_response — plasma concentration over time (one-compartment model, single or repeated doses, therapeutic window) and the Hill curve with a competitive antagonist.

  • calculate_solution, calculate_content, calculate_pharmacokinetics — what to weigh and how to dilute; content determinations with Grubbs test, t-test, fat characteristics and Karl Fischer; half-life, AUC, steady state and loading dose, each with the working.

To switch, set CHEMDRAW_PROFILE and restart the server:

uv run chemdraw-tool-server                         # mvp, the default
CHEMDRAW_PROFILE=full uv run chemdraw-tool-server   # all 23 tools

For Claude Desktop, add "env": {"CHEMDRAW_PROFILE": "full"} to the server entry in claude_desktop_config.json and restart Claude Desktop. An invalid profile name stops startup with an error. Two optional vault tools (search_vault, read_vault_entry) appear only in the full profile and only when CHEMDRAW_VAULT_PATH is set.

Installation

Pick one route — installing twice registers the server twice and the model sees every tool doubled. Afterwards restart Claude Desktop and ask "draw caffeine".

1. Claude Desktop extension (macOS, Linux)

Download chemdraw-mcp-<version>.mcpb from the latest release, double-click it and confirm in Claude Desktop, then restart Claude Desktop once. The first start fetches the package from PyPI via uv, every file checked against hashes pinned at release time (a missing uv is downloaded at a fixed version and its SHA-256 verified). That is about 40 MB and takes a minute; later starts are offline.

If your organization manages Claude Desktop, it may block extensions or allow only listed ones — then use route 2.

2. From PyPI

Needs uv:

uv tool install chemdraw-mcp
chemdraw-install

chemdraw-install adds the Claude Desktop entry with the absolute path of the installed launcher, backs up the config first, leaves other MCP servers untouched and prints what it registered.

git clone https://github.com/jurimaxam-dotcom/chemdraw-mcp.git
cd chemdraw-mcp && ./install.sh

install.sh installs uv if missing, syncs the dependencies and registers the server the same way chemdraw-install does.

Add this to claude_desktop_config.json under mcpServers (macOS: ~/Library/Application Support/Claude/claude_desktop_config.json):

"chemdraw-tool": {
  "command": "/opt/homebrew/bin/uvx",
  "args": ["chemdraw-mcp"]
}

Claude Desktop starts MCP servers with a minimal PATH, not your login shell. A bare "uvx" cannot be found there and the server fails without a message. Put the absolute path that which uvx prints on your machine into command.

Optional extras

  • A Java runtime (e.g. brew install openjdk) lets OPSIN parse systematic IUPAC names offline, including names no database indexes. Without Java, names are resolved online through PubChem and NCI.

  • The AnkiConnect add-on lets export_anki_deck add cards to a running Anki. Without it you import the .apkg file yourself.

  • ChemDraw is never required. Request formats=["cdxml"] to continue editing a structure there.

Something not working? Run the doctor

chemdraw-doctor                            # after "uv tool install chemdraw-mcp"
uv run chemdraw-doctor                     # in a clone
uvx --from chemdraw-mcp chemdraw-doctor    # without installing anything

It checks the six things that make the server look dead in the chat — RDKit rendering, the Java/OPSIN runtime, the uv path, the Claude Desktop entry, the name databases and the output directory — and prints the command that fixes each problem. Results are [OK], [LIMITED] (works, but restricted), [FAIL] or [NOTE] (does not apply). The exit code stays 0 while the server is usable. From a PyPI install the uv and Claude Desktop checks report [NOTE], because they belong to the repository installer.

If the server code or a dependency changed, restart Claude Desktop: it keeps the server process running, and an old process mixed with new files fails in confusing ways.

Limitations

  • Without Java, names need the internet. OPSIN is skipped and names are resolved online through PubChem and NCI, so only names those databases index are found. SMILES input never touches the network.

  • Lab graphics are drawings of given numbers. Spectra, TLC plates and pH curves show the values passed in. They measure nothing; values the model supplied from memory need checking. TLC spot intensity is a drawing hint, not densitometry.

  • Mechanisms are three fixed examples (SN1, SN2, Fischer esterification).

  • 3D is one conformer, a plausible geometry to look at — not a conformational search and not an energy statement.

  • CDXML is a side path. It is round-trip validated, but PNG and SVG are the primary outputs and the ones the pixel tests cover.

  • The extension targets macOS and Linux. Windows is untested.

How it works

name / SMILES
   │
   ▼
resolver ──► OPSIN (systematic IUPAC names, offline) ──► PubChem / NCI (names)  ·  direct parse (SMILES)
   │
   ▼
RDKit 2D coordinates ──► validation (sanity, round-trip)
   │
   ├──► image_export   → PNG + SVG files          (primary, offline)
   ├──► svg_renderer   → interactive chat preview (MCP App resource)
   └──► cdxml_writer   → ChemDraw CDXML           (optional, on request)

The lab graphics (spectrum.py, tlc.py, ph_plots.py) render with matplotlib; the panel is a React app served by the server as an MCP App resource.

Development

Python 3.11+, package manager uv.

uv sync                      # backend dependencies
cd chemdraw_tool/ui && npm install && npx playwright install chromium  # frontend, once
./test.sh                    # the gate: lint, pytest, bundle freshness, JS unit and browser tests

About 7,500 Python tests plus JavaScript unit and headless-Chromium tests, written test-first. Frozen renderings guard the drawing output, a pinned identity list guards name resolution, and snapshots of every tool description guard which tool the model picks.

Feedback, bugs and wishes

  • Something broke? Open a bug report — the form asks for the output of chemdraw-doctor.

  • Missing something in your course? Tell us what you would draw or calculate — the subject and the exam question help more than a feature name.

  • Wrong chemistry? Use the bug form and name the compound and the figure.

  • A question, or something you made with it? Discussions.

  • It worked for you? A ⭐ on the repository helps other students find it.

License

Apache-2.0 — see LICENSE. Copyright 2026 jurimaxam-dotcom.

Disclaimer: This is an unofficial, independent project, not affiliated with or endorsed by Revvity. ChemDraw is a trademark of Revvity Signals Software, Inc. This tool does not include or require ChemDraw; it can optionally export files in the open CDXML format.

Available Tools

7 tools
batch_generateA

Draw several individual compounds as separate PNG/SVG files and panels.

Failed names are reported in failed while successful structures are returned. Pass English or IUPAC names, or SMILES.

Not this tool for: one compound (use generate_molecule), structural differences (use compare_molecules), or a reaction scheme (use generate_reaction).

Args: molecules: List of English/IUPAC compound names or SMILES strings. formats: Output file formats, any of "png", "svg", "cdxml" (default: ["png", "svg"]). Include "cdxml" ONLY when the user wants to edit the structures in ChemDraw. abbreviate_groups: Set True to draw common substituents as short labels (Ph, Bn, OAc, OMe, CO2H, tBu, Boc, Ts …) instead of full skeletons. Applies to every molecule in the batch, so a series of structures stays visually consistent. render_style: Named look applied to every molecule in the batch. Empty = standard style. "compact" for small printed figures, "presentation" for slides, "grayscale" for grayscale printing.

NameRequiredDescriptionDefault
formatsNo
moleculesYes
render_styleNo
annotate_stereoNo
abbreviate_groupsNo

Output Schema

NameRequiredDescription
typeNo
failedNo
moleculesNo
cdxml_pathsNo

TDQS

A4.8/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Since no annotations are provided, the description carries the full burden and performs well. It explicitly details a key behavioral trait: failed names are reported while successful structures are returned. It also explains the conditional use of 'cdxml' for ChemDraw editing.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The tool definition is structured logically, starting with the core function, then providing limitations, and finally detailing parameters. Every section is tightly written and efficiently organized.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of handling batch processing, multiple formats, and custom rendering, the description is remarkably complete. It provides all the necessary context and constraints for an agent to invoke the tool correctly despite the sparse structured data.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Despite having 0% schema description coverage, the description provides high-value semantic context for every parameter. For instance, it explains the functional difference between 'abbreviate_groups' (consistency) and 'render_style' (use case for printing/slides), adding meaning far beyond the schema data.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The purpose is highly specific: drawing multiple individual compounds as PNG/SVG files and panels. It clearly distinguishes itself from sibling tools by stating it is not suitable for single compounds (use generate_molecule), reaction schemes, or structural comparisons.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The tool explicitly forbids certain use cases, detailing that it should not be used for single molecules, structural differences, or reaction schemes. It provides direct redirection to the correct alternative sibling tool for each specific scenario.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

compare_moleculesA

Compare 2-4 molecules side by side with their DIFFERENCES highlighted.

Computes the maximum common substructure (MCS): the shared scaffold stays neutral, everything outside it is highlighted — ideal for teaching drug classes ("what distinguishes ibuprofen from naproxen?"), homologous series or derivatives.

Use this when the user wants to compare structures, see differences between compounds, or study a drug class.

Reach for it in conversation too, not only on request: the word "difference" in a question about two substances is the trigger. Answering "what distinguishes ibuprofen from naproxen?" in prose leaves the reader to find the difference in two separate pictures — this figure marks it.

Not this tool for: a single structure (generate_molecule), or several structures that are merely to be drawn rather than contrasted (batch_generate).

Args: structures: 2-4 English/IUPAC names or SMILES strings. labels: Optional display names under each panel (localizable). title: Optional heading for the comparison (localizable).

NameRequiredDescriptionDefault
titleNo
labelsNo
structuresYes

Output Schema

NameRequiredDescription
svgNo
nameYes
typeNo
filesNo
notesNo
subtitleNo

TDQS

A4.6/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations exist, so the description carries the full load — it discloses the algorithmic behavior (MCS computed, shared scaffold kept neutral for contrast) and that the result is a figure rather than prose, which is meaningful behavioral context. It stops short of stating failure behavior for unresolvable names or whether a file is written, which are the remaining gaps for an annotation-free tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core definition, then usage, then exclusions, then args — a rational order with clear sectioning. The conversational-trigger paragraph is slightly padded and repeats the ibuprofen/naproxen example already used earlier, costing a point.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present, return values need no explanation, and the description covers scope, exclusions, and all three parameters. The only thin spot is edge-case behavior — what happens with fewer than 2 structures, more than 4, or an unresolvable name.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate, and it does: structures accepts 2-4 English/IUPAC names or SMILES, labels are per-panel display names that are localizable, and title is an optional localizable heading. This adds real meaning beyond the bare schema types and closes the coverage gap.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Compare 2-4 molecules side by side') and explains the mechanism (maximum common substructure with non-shared parts highlighted), which tells the agent exactly what the output depicts. It also names the siblings it is not (generate_molecule, batch_generate), so it is distinguishable without opening any schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives explicit when-to-use triggers ('user wants to compare structures', 'study a drug class'), an explicit not-for clause with named alternatives for both exclusions, and even a conversational trigger word ('difference'). Nothing is left to inference.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

export_anki_deckA

Export an Anki flashcard deck (.apkg) with rendered chemistry images.

Use this whenever the user wants flashcards, Anki cards or a study deck for molecules, reactions (e.g. pharmacopoeia identity tests) or spectra. A stated intention to learn or an exam coming up is the same request: offer a deck and write the cards yourself.

Two ways to fill the deck. Either pass cards you wrote yourself, or pass curated_deck_id for a ready-made, formula-verified starter deck:

  • "analgesics-structures": structure → name drills for 8 classic analgesics (NSAIDs, paracetamol, morphine, celecoxib).

  • "pheur-identity-basics": classic Ph.Eur. identity tests — reagent, observation and reaction scheme where it helps.

The tool renders the images — YOU supply the card content from your knowledge. Each card side carries text plus at most ONE visual: structure (name or SMILES), reaction ({reactants, products, conditions}) or spectrum ({spectrum_type, peaks, title}). Proven types: structure↔name, identity reactions (question front, scheme back), functional-group recognition, band assignment, name drills.

Re-exporting under the SAME deck name updates existing cards instead of duplicating them — the front identifies the card.

Options: reversed=true drills both directions (one note, two cards); cloze=true makes fill-in-the-blank cards (front.text carries {{c1::...}}, back.text becomes the extra note). "Parent::Child" nests subdecks.

IMPORTANT: structures take English/IUPAC names or SMILES; card TEXTS may be localized. Never deliver via AnkiConnect unless asked.

Args: deck_name: Deck name, also the filename; re-use it to update a deck. Ignored when curated_deck_id is set. cards: The flashcards. Fronts unambiguous, explanations on the back. default_tags: Tags added to every card. deliver: "apkg" (file only), "open" (also opens it in Anki, macOS) or "ankiconnect" (imports via the AnkiConnect add-on). curated_deck_id: "analgesics-structures" or "pheur-identity-basics".

NameRequiredDescriptionDefault
cardsNo
deliverNoapkg
deck_nameNo
default_tagsNo
curated_deck_idNo

Output Schema

NameRequiredDescription
fileNo
nameYes
typeNo
cardsYes
mediaYes
frontsNo
deliveryNo

TDQS

A4.9/5.0
Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does it well: same deck name updates rather than duplicates (front is the key), `deck_name` is ignored when `curated_deck_id` is set, `deliver` has three concrete modes, `reversed` produces one note/two cards, `cloze` changes what front/back mean, and 'Parent::Child' nests subdecks. These are non-obvious side effects an agent could not infer from the schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Long but front-loaded and segmented: purpose first, then triggers, then the two fill paths, then card anatomy, then options, then per-argument notes. Every paragraph answers a distinct question an agent would otherwise have to guess at.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a complex nested-card export tool with 5 params, the description covers card construction, proven card types, update semantics and delivery modes; the output schema relieves it of explaining return values. Minor gap: it doesn't say what happens if neither `cards` nor `curated_deck_id` is supplied, nor where the .apkg file is written.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0% at the top level, but the Args block documents all five parameters, including the enum-like values for `deliver` and `curated_deck_id` that the schema does not constrain. The card-side constraint (text plus at most ONE visual, with the shapes of structure/reaction/spectrum) supplies the nesting semantics the schema leaves implicit.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and artifact: 'Export an Anki flashcard deck (.apkg) with rendered chemistry images.' It also clarifies the division of labour (tool renders images, the agent supplies card content), which no sibling tool does.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly names the triggering situations (flashcards, study deck, exam coming up, intent to learn) and routes between the two fill modes: own `cards` vs `curated_deck_id`. It also states an exclusion ('Never deliver via AnkiConnect unless asked') and names both curated deck IDs with their contents.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

generate_moleculeA

Draw one compound as a 2D structure — the default for a single substance.

Writes PNG/SVG files and returns an interactive panel with the structure, properties and functional groups. A bare compound name ("caffeine") also means this tool, and so does a question about why one compound behaves as it does (acidity, solubility) — the answer is in its structure. No ChemDraw required. A Fischer or Haworth projection of a sugar or amino acid, or a drawing with all H atoms, is this tool too: set view to "fischer", "haworth" or "all_h".

Not this tool for: several individual structures (use batch_generate), structural differences (use compare_molecules), a reaction scheme (use generate_reaction), or a data sheet (use lookup_molecule_data).

Pass English or IUPAC names, or SMILES; use label for a localized display name.

Args: name_or_smiles: English/IUPAC compound name or SMILES string. label: Display name shown below the structure (may be localized). formats: Any of "png", "svg", "cdxml" (default: png + svg). Add "cdxml" only when the structure is to be edited in ChemDraw. annotate_stereo: True prints CIP descriptors (R/S, E/Z) at each stereocenter. abbreviate_groups: True draws common substituents as the short labels chemists write by hand (Ph, Bn, OAc, OMe, CO2H, NO2, tBu, Boc, Ts, TMS). The chemistry is unchanged; no hover tooltips in the panel. render_style: "" standard · "compact" thin bonds for small print · "presentation" thick bonds for slides · "grayscale" b/w palette. stereo_variants: True returns every stereoisomer of the open centers (max 3) as a pick list instead of a drawing; only on request. view: "fischer"/"haworth"/"all_h" opens on that drawing, only if the user names it.

NameRequiredDescriptionDefault
viewNo
labelNo
formatsNo
render_styleNo
name_or_smilesYes
annotate_stereoNo
stereo_variantsNo
abbreviate_groupsNo

Output Schema

NameRequiredDescription
svgNo
nameNo
typeNo
atomsNo
filesNo
viewsNo
messageNo
viewSvgNo
lipinskiNo
subtitleNo
viewAtomsNo
candidatesNo
cdxml_pathNo
propertiesNo
stereoNoteNo
initialViewNo
viewRequestNo
projectionNoteNo
stereoWarningsNo
functionalGroupsNo

TDQS

A4.7/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and does well: it discloses the file side effects (writes PNG/SVG), the return artifact (interactive panel with structure, properties, functional groups), and non-obvious behavioral consequences per flag (abbreviate_groups kills hover tooltips; stereo_variants returns a pick list instead of a drawing). It stops short of error behavior for invalid names/SMILES or whether existing files are overwritten.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Roughly front-loaded: purpose first, then routing, then args. Minor redundancy — the fischer/haworth/all_h options are stated once in prose and again under view — and 'No ChemDraw required' is filler, but no sentence is genuinely wasteful.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Eight parameters, no annotations, and an output schema. The description covers routing, all parameter semantics, side effects, and the return artifact, so an agent can call it correctly without reading anything else.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must supply all meaning, and it does: formats lists allowed values and the default, view names its three accepted values, render_style enumerates all four modes with intent, and the boolean flags each explain their effect (CIP R/S and E/Z labels; abbreviation set Ph/Bn/OAc/...; max 3 stereoisomer pick list).

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The opening sentence gives a specific verb and resource ('draw one compound as a 2D structure') plus its scope ('the default for a single substance'). It then enumerates non-obvious inputs that also route here (bare compound name, a behavior question like acidity/solubility, Fischer/Haworth projections) and names each sibling that handles the other cases.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

An explicit 'Not this tool for:' block routes to batch_generate (several structures), compare_molecules (differences), generate_reaction (reaction schemes) and lookup_molecule_data (data sheets). Positive triggers are also given, including indirect ones like a question about why a compound behaves as it does.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

generate_reactionA

Draw a reaction scheme from reactants, products and conditions.

Writes PNG/SVG files and returns a panel with conditions above and below the arrow. arrow: "forward" (→), "equilibrium" (⇌, reversible) or "retro" (⇒). Use it when explaining a reaction as well as for explicit drawing requests. This draws the net reaction, without step-by-step electron-flow mechanisms. Pass English or IUPAC compound names, or SMILES.

Not this tool for: one compound or a property of one compound such as its acidity (use generate_molecule), independent structures (use batch_generate), or structural differences (use compare_molecules).

Args: reactants: List of English/IUPAC reactant names or SMILES strings. products: List of English/IUPAC product names or SMILES strings. conditions: Text above the arrow (e.g. 'H2SO4, 0-5 °C'); formula digits are subscripted, a line break starts a new line. conditions_below: Text under the arrow (e.g. 'reflux, 2 h'). arrow: "forward" (→), "equilibrium" (⇌, reversible reaction) or "retro" (⇒, retrosynthesis: target as reactants, precursors as products). name: Display name for the reaction step (can be localized). formats: Any of "png", "svg", "cdxml" (default: png + svg). Add "cdxml" only when the scheme is to be edited in ChemDraw. abbreviate_groups: True draws common substituents as short labels (Ph, OAc, OMe, CO2H, tBu, Boc …); the CDXML keeps full structures. render_style: "" standard · "compact" small print · "presentation" slides · "grayscale" b/w palette. coefficients: One integer per species, reactants then products ([2, 1, 2] draws 2 H2 + O2 → 2 H2O). Set only when the user asks for a balanced equation; otherwise draw as given — the panel's "Apply coefficients" button sets them.

NameRequiredDescriptionDefault
nameNo
arrowNoforward
formatsNo
productsYes
reactantsYes
conditionsNo
coefficientsNo
render_styleNo
conditions_belowNo
abbreviate_groupsNo

Output Schema

NameRequiredDescription
nameNo
typeNo
arrowNo
filesNo
balanceNo
requestNo
productsNo
reactantsNo
cdxml_pathNo
conditionsNo
coefficientsNo
conditions_belowNo

TDQS

A4.7/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description does the heavy lifting: it discloses side effects (writes PNG/SVG/CDXML files), the return artifact (a panel with conditions above/below the arrow), and a limitation (no electron-flow mechanisms). It also warns that coefficients are only applied on request and that the CDXML keeps full structures under abbreviation. Missing only concrete file locations or overwrite behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose, then exclusions, then a per-argument list — easy to scan. It loses a point for duplicating the arrow enum definition verbatim in both the opening paragraph and the Args block.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 10-parameter generative tool with an output schema, everything an agent needs is present: triggers, exclusions, input formats, output formats and defaults. Return value explanation is correctly omitted since an output schema exists.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, and the description fully compensates: it defines every non-obvious parameter, gives the enum meanings for arrow with glyphs and the retro semantics, enumerates formats with a default, explains render_style values, and specifies coefficients ordering ('reactants then products') with a worked example.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

Opens with a specific verb+resource ('Draw a reaction scheme from reactants, products and conditions') and immediately scopes it as the net reaction rather than a mechanism. Explicitly names each sibling it is not for and what to use instead.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives both a positive trigger ('Use it when explaining a reaction as well as for explicit drawing requests') and an explicit exclusion block listing generate_molecule, batch_generate and compare_molecules with the condition that selects each.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

lookup_molecule_dataA

Show a compound's data sheet: structure, PubChem properties and GHS safety.

Use it for a data sheet or facts available from those sources. The molecule panel also calls this tool when the user clicks Data. Internet access is required. Missing values are not evidence that a property or hazard is absent.

Not this tool for: a bare compound name with no data requested — use generate_molecule. Pass English or IUPAC names, or SMILES.

Args: name: English/IUPAC compound name or SMILES (e.g. 'Aspirin').

NameRequiredDescriptionDefault
nameYes

Output Schema

NameRequiredDescription
nameNo
typeNo
atomsNo
smilesNo
sourcesNo
stereoNoteNo
molecule_svgNo
stereoWarningsNo
functionalGroupsNo

TDQS

A4.8/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Since no annotations were provided, the description carries the full burden of transparency. It explicitly states that 'Missing values are not evidence that a property or hazard is absent,' which is a critical behavioral caveat for a lookup tool pulling external data. It also notes the dependency on internet access.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is highly efficient. Every sentence adds value, moving from primary function to operational requirements, exclusions, and finally, parameter guidance.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the critical nature of distinguishing it from `generate_molecule` and specifying input formats (SMILES/IUPAC/English), the description is maximally complete for an AI agent attempting correct tool selection.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema is extremely sparse (just 'name': 'string'). The description significantly enhances the schema by detailing that 'name' can be an English/IUPAC compound name or a SMILES string, providing concrete examples like 'Aspirin' to guide usage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The purpose is immediately clear: to show a compound's data sheet including structure, PubChem properties, and GHS safety. It successfully differentiates itself from sibling tools by specifying its function as data retrieval.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The tool provides explicit instructions on when to use it and when *not* to use it, referring the agent to `generate_molecule` for bare compound names. It also adds the necessary operational constraint: internet access is required.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

save_pngA

Internal helper for the panel UI — never call this directly.

The panel's export button calls it when the image clipboard is blocked by the sandbox; saving a picture is the user's click, not yours. The generate_* tools already write their PNG and SVG files themselves.

Expects a base64 PNG (with or without a data:image/png;base64, prefix) and returns the path it was written to.

NameRequiredDescriptionDefault
filenameYes
png_base64Yes

Output Schema

NameRequiredDescription
resultYes

TDQS

A4.4/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the behavioral burden and does disclose the invocation context, the clipboard/sandbox condition, accepted input format, and that it returns the written path. It does not mention overwrite behavior, permissions, or error handling for file writes, which are relevant gaps for a save operation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The warning not to call the tool is front-loaded, and the remaining sentences are short and purposeful. Every sentence adds either usage context or a relevant input/output detail without repetition.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so the description need not explain return values in detail, and it already states that a path is returned. For a two-parameter internal helper it is largely complete, though filename semantics remain underspecified.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate. It partially does by explaining that png_base64 is a base64 PNG with an optional data:image/png;base64, prefix, but it says nothing about the filename parameter's expected path, directory, extension, or overwrite semantics.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific action (save a PNG), the expected input (base64 PNG), and the result (returns the written path). It also explicitly distinguishes this from the generate_* tools, which already write their own PNG and SVG files, so an agent can tell this is not the normal image-generation path.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It gives an unusually explicit usage rule: never call this directly, because the panel's export button invokes it when sandbox clipboard access is blocked. It also names the relevant alternative behavior by noting that generate_* tools already write their files themselves.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Tool Schema Changelog

Recent tool additions, removals, and schema changes observed during successful MCP inspections.

  1. 4 tool updatesv0.6.0
    • Changedbatch_generate12 fields changed
      • addedOutput schema / $defs / IsomerCandidate
        Added value: +{
        +  "description": "One structure a family name (\"xylene\", \"Glucose\") can mean.",
        +  "properties": {
        +    "label": {
        +      "title": "Label",
        +      "type": "string"
        +    },
        +    "name": {
        +      "default": "",
        +      "title": "Name",
        +      "type": "string"
        +    },
        +    "smiles": {
        +      "title": "Smiles",
        +      "type": "string"
        +    },
        +    "svg": {
        +      "default": "",
        +      "title": "Svg",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "label",
        +    "smiles"
        +  ],
        +  "title": "IsomerCandidate",
        +  "type": "object"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / candidates
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/IsomerCandidate"
        +  },
        +  "title": "Candidates",
        +  "type": "array"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / initialView
        Added value: +{
        +  "default": "",
        +  "title": "Initialview",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / message
        Added value: +{
        +  "default": "",
        +  "title": "Message",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / projectionNote
        Added value: +{
        +  "default": "",
        +  "title": "Projectionnote",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / stereoNote
        Added value: +{
        +  "default": "",
        +  "title": "Stereonote",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / stereoWarnings
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/StereoWarning"
        +  },
        +  "title": "Stereowarnings",
        +  "type": "array"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / viewAtoms
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/AtomData"
        +  },
        +  "title": "Viewatoms",
        +  "type": "array"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / viewRequest
        Added value: +{
        +  "additionalProperties": true,
        +  "default": {},
        +  "title": "Viewrequest",
        +  "type": "object"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / viewSvg
        Added value: +{
        +  "default": "",
        +  "title": "Viewsvg",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / MoleculePayload / properties / views
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "type": "string"
        +  },
        +  "title": "Views",
        +  "type": "array"
        +}
      • addedOutput schema / $defs / StereoWarning
        Added value: +{
        +  "description": "Ein Stereoelement, dessen Konfiguration die Eingabe offen lässt.",
        +  "properties": {
        +    "atoms": {
        +      "default": [],
        +      "items": {
        +        "type": "integer"
        +      },
        +      "title": "Atoms",
        +      "type": "array"
        +    },
        +    "kind": {
        +      "title": "Kind",
        +      "type": "string"
        +    },
        +    "label": {
        +      "default": "",
        +      "title": "Label",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "kind"
        +  ],
        +  "title": "StereoWarning",
        +  "type": "object"
        +}
    • Changedgenerate_molecule14 fields changed
      • addedInput schema / properties / stereo_variants
        Added value: +{
        +  "default": false,
        +  "title": "Stereo Variants",
        +  "type": "boolean"
        +}
      • addedInput schema / properties / view
        Added value: +{
        +  "default": "",
        +  "title": "View",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / IsomerCandidate
        Added value: +{
        +  "description": "One structure a family name (\"xylene\", \"Glucose\") can mean.",
        +  "properties": {
        +    "label": {
        +      "title": "Label",
        +      "type": "string"
        +    },
        +    "name": {
        +      "default": "",
        +      "title": "Name",
        +      "type": "string"
        +    },
        +    "smiles": {
        +      "title": "Smiles",
        +      "type": "string"
        +    },
        +    "svg": {
        +      "default": "",
        +      "title": "Svg",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "label",
        +    "smiles"
        +  ],
        +  "title": "IsomerCandidate",
        +  "type": "object"
        +}
      • addedOutput schema / $defs / StereoWarning
        Added value: +{
        +  "description": "Ein Stereoelement, dessen Konfiguration die Eingabe offen lässt.",
        +  "properties": {
        +    "atoms": {
        +      "default": [],
        +      "items": {
        +        "type": "integer"
        +      },
        +      "title": "Atoms",
        +      "type": "array"
        +    },
        +    "kind": {
        +      "title": "Kind",
        +      "type": "string"
        +    },
        +    "label": {
        +      "default": "",
        +      "title": "Label",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "kind"
        +  ],
        +  "title": "StereoWarning",
        +  "type": "object"
        +}
      • addedOutput schema / properties / candidates
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/IsomerCandidate"
        +  },
        +  "title": "Candidates",
        +  "type": "array"
        +}
      • addedOutput schema / properties / initialView
        Added value: +{
        +  "default": "",
        +  "title": "Initialview",
        +  "type": "string"
        +}
      • addedOutput schema / properties / message
        Added value: +{
        +  "default": "",
        +  "title": "Message",
        +  "type": "string"
        +}
      • addedOutput schema / properties / projectionNote
        Added value: +{
        +  "default": "",
        +  "title": "Projectionnote",
        +  "type": "string"
        +}
      • addedOutput schema / properties / stereoNote
        Added value: +{
        +  "default": "",
        +  "title": "Stereonote",
        +  "type": "string"
        +}
      • addedOutput schema / properties / stereoWarnings
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/StereoWarning"
        +  },
        +  "title": "Stereowarnings",
        +  "type": "array"
        +}
      • addedOutput schema / properties / viewAtoms
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/AtomData"
        +  },
        +  "title": "Viewatoms",
        +  "type": "array"
        +}
      • addedOutput schema / properties / viewRequest
        Added value: +{
        +  "additionalProperties": true,
        +  "default": {},
        +  "title": "Viewrequest",
        +  "type": "object"
        +}
      • addedOutput schema / properties / viewSvg
        Added value: +{
        +  "default": "",
        +  "title": "Viewsvg",
        +  "type": "string"
        +}
      • addedOutput schema / properties / views
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "type": "string"
        +  },
        +  "title": "Views",
        +  "type": "array"
        +}
    • Changedgenerate_reaction10 fields changed
      • addedInput schema / properties / arrow
        Added value: +{
        +  "default": "forward",
        +  "enum": [
        +    "forward",
        +    "equilibrium",
        +    "retro"
        +  ],
        +  "title": "Arrow",
        +  "type": "string"
        +}
      • addedInput schema / properties / coefficients
        Added value: +{
        +  "anyOf": [
        +    {
        +      "items": {
        +        "type": "integer"
        +      },
        +      "type": "array"
        +    },
        +    {
        +      "type": "null"
        +    }
        +  ],
        +  "default": null,
        +  "title": "Coefficients"
        +}
      • addedInput schema / properties / conditions_below
        Added value: +{
        +  "default": "",
        +  "title": "Conditions Below",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / MolEntry / properties / coefficient
        Added value: +{
        +  "default": 1,
        +  "title": "Coefficient",
        +  "type": "integer"
        +}
      • addedOutput schema / $defs / ReactionBalance
        Added value: +{
        +  "description": "Atom and charge balance of the equation as drawn (all coefficients 1).",
        +  "properties": {
        +    "balanced": {
        +      "title": "Balanced",
        +      "type": "boolean"
        +    },
        +    "chargeDifference": {
        +      "default": 0,
        +      "title": "Chargedifference",
        +      "type": "integer"
        +    },
        +    "difference": {
        +      "additionalProperties": {
        +        "type": "integer"
        +      },
        +      "default": {},
        +      "title": "Difference",
        +      "type": "object"
        +    },
        +    "formulas": {
        +      "default": [],
        +      "items": {
        +        "type": "string"
        +      },
        +      "title": "Formulas",
        +      "type": "array"
        +    },
        +    "note": {
        +      "default": "",
        +      "title": "Note",
        +      "type": "string"
        +    },
        +    "suggestedCoefficients": {
        +      "anyOf": [
        +        {
        +          "items": {
        +            "type": "integer"
        +          },
        +          "type": "array"
        +        },
        +        {
        +          "type": "null"
        +        }
        +      ],
        +      "default": null,
        +      "title": "Suggestedcoefficients"
        +    },
        +    "suggestedEquation": {
        +      "default": "",
        +      "title": "Suggestedequation",
        +      "type": "string"
        +    },
        +    "summary": {
        +      "default": "",
        +      "title": "Summary",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "balanced"
        +  ],
        +  "title": "ReactionBalance",
        +  "type": "object"
        +}
      • addedOutput schema / properties / arrow
        Added value: +{
        +  "default": "forward",
        +  "title": "Arrow",
        +  "type": "string"
        +}
      • addedOutput schema / properties / balance
        Added value: +{
        +  "anyOf": [
        +    {
        +      "$ref": "#/$defs/ReactionBalance"
        +    },
        +    {
        +      "type": "null"
        +    }
        +  ],
        +  "default": null
        +}
      • addedOutput schema / properties / coefficients
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "type": "integer"
        +  },
        +  "title": "Coefficients",
        +  "type": "array"
        +}
      • addedOutput schema / properties / conditions_below
        Added value: +{
        +  "default": "",
        +  "title": "Conditions Below",
        +  "type": "string"
        +}
      • addedOutput schema / properties / request
        Added value: +{
        +  "additionalProperties": true,
        +  "default": {},
        +  "title": "Request",
        +  "type": "object"
        +}
    • Changedlookup_molecule_data9 fields changed
      • addedOutput schema / $defs / DatabaseSource / properties / groups
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/GhsGroup"
        +  },
        +  "title": "Groups",
        +  "type": "array"
        +}
      • addedOutput schema / $defs / DatabaseSource / properties / note
        Added value: +{
        +  "default": "",
        +  "title": "Note",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / DatabaseSource / properties / status
        Added value: +{
        +  "default": "",
        +  "title": "Status",
        +  "type": "string"
        +}
      • addedOutput schema / $defs / GhsGroup
        Added value: +{
        +  "description": "Die Einstufung EINER Quelle (PubChem ReferenceNumber).",
        +  "properties": {
        +    "hazards": {
        +      "default": [],
        +      "items": {
        +        "$ref": "#/$defs/GhsHazard"
        +      },
        +      "title": "Hazards",
        +      "type": "array"
        +    },
        +    "id": {
        +      "title": "Id",
        +      "type": "string"
        +    },
        +    "lead": {
        +      "default": false,
        +      "title": "Lead",
        +      "type": "boolean"
        +    },
        +    "not_classified": {
        +      "anyOf": [
        +        {
        +          "$ref": "#/$defs/GhsNotClassified"
        +        },
        +        {
        +          "type": "null"
        +        }
        +      ],
        +      "default": null
        +    },
        +    "note": {
        +      "default": "",
        +      "title": "Note",
        +      "type": "string"
        +    },
        +    "p_codes": {
        +      "default": [],
        +      "items": {
        +        "type": "string"
        +      },
        +      "title": "P Codes",
        +      "type": "array"
        +    },
        +    "pictograms": {
        +      "default": [],
        +      "items": {
        +        "type": "string"
        +      },
        +      "title": "Pictograms",
        +      "type": "array"
        +    },
        +    "record_name": {
        +      "default": "",
        +      "title": "Record Name",
        +      "type": "string"
        +    },
        +    "reports_total": {
        +      "anyOf": [
        +        {
        +          "type": "integer"
        +        },
        +        {
        +          "type": "null"
        +        }
        +      ],
        +      "default": null,
        +      "title": "Reports Total"
        +    },
        +    "signal": {
        +      "default": "",
        +      "title": "Signal",
        +      "type": "string"
        +    },
        +    "source": {
        +      "title": "Source",
        +      "type": "string"
        +    },
        +    "url": {
        +      "default": "",
        +      "title": "Url",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "id",
        +    "source"
        +  ],
        +  "title": "GhsGroup",
        +  "type": "object"
        +}
      • addedOutput schema / $defs / GhsHazard
        Added value: +{
        +  "properties": {
        +    "code": {
        +      "title": "Code",
        +      "type": "string"
        +    },
        +    "percent": {
        +      "anyOf": [
        +        {
        +          "type": "number"
        +        },
        +        {
        +          "type": "null"
        +        }
        +      ],
        +      "default": null,
        +      "title": "Percent"
        +    },
        +    "text": {
        +      "default": "",
        +      "title": "Text",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "code"
        +  ],
        +  "title": "GhsHazard",
        +  "type": "object"
        +}
      • addedOutput schema / $defs / GhsNotClassified
        Added value: +{
        +  "description": "Eine Quelle meldet ausdruecklich \"erfuellt die GHS-Kriterien nicht\".",
        +  "properties": {
        +    "percent": {
        +      "anyOf": [
        +        {
        +          "type": "number"
        +        },
        +        {
        +          "type": "null"
        +        }
        +      ],
        +      "default": null,
        +      "title": "Percent"
        +    },
        +    "reports": {
        +      "anyOf": [
        +        {
        +          "type": "integer"
        +        },
        +        {
        +          "type": "null"
        +        }
        +      ],
        +      "default": null,
        +      "title": "Reports"
        +    },
        +    "total": {
        +      "anyOf": [
        +        {
        +          "type": "integer"
        +        },
        +        {
        +          "type": "null"
        +        }
        +      ],
        +      "default": null,
        +      "title": "Total"
        +    }
        +  },
        +  "title": "GhsNotClassified",
        +  "type": "object"
        +}
      • addedOutput schema / $defs / StereoWarning
        Added value: +{
        +  "description": "Ein Stereoelement, dessen Konfiguration die Eingabe offen lässt.",
        +  "properties": {
        +    "atoms": {
        +      "default": [],
        +      "items": {
        +        "type": "integer"
        +      },
        +      "title": "Atoms",
        +      "type": "array"
        +    },
        +    "kind": {
        +      "title": "Kind",
        +      "type": "string"
        +    },
        +    "label": {
        +      "default": "",
        +      "title": "Label",
        +      "type": "string"
        +    }
        +  },
        +  "required": [
        +    "kind"
        +  ],
        +  "title": "StereoWarning",
        +  "type": "object"
        +}
      • addedOutput schema / properties / stereoNote
        Added value: +{
        +  "default": "",
        +  "title": "Stereonote",
        +  "type": "string"
        +}
      • addedOutput schema / properties / stereoWarnings
        Added value: +{
        +  "default": [],
        +  "items": {
        +    "$ref": "#/$defs/StereoWarning"
        +  },
        +  "title": "Stereowarnings",
        +  "type": "array"
        +}
  2. 7 tool updatesv0.1.0
    • First observedbatch_generate
    • First observedcompare_molecules
    • First observedexport_anki_deck
    • First observedgenerate_molecule
    • First observedgenerate_reaction
    • First observedlookup_molecule_data
    • First observedsave_png

TDQS

A4.6/5.0

Scored across 7 tools

Disambiguation5/5

Each tool has a clearly distinct purpose, and the descriptions explicitly cross-reference when to use another tool (single vs. batch, compare vs. draw, reaction vs. molecule, data sheet vs. bare name). The only internal helper, save_png, is explicitly marked as never called directly, so it does not create ambiguity.

Naming Consistency4/5

All names use snake_case and are mostly verb-first (generate_molecule, lookup_molecule_data, generate_reaction, compare_molecules, export_anki_deck, save_png). The only minor deviation is batch_generate, where the verb is not first, but the convention remains readable and predictable overall.

Tool Count5/5

Seven tools is well within the appropriate range and each tool covers a distinct workflow: single drawing, batch drawing, reaction drawing, comparison, data lookup, Anki export, and an internal save helper. The set feels scoped rather than bloated or thin.

Completeness4/5

The surface covers the core chemical drawing lifecycle: single structures, batches, reactions, side-by-side comparison, external data lookup, and flashcard export. Minor gaps exist, such as no dedicated spectrum-generation tool despite spectra being supported in Anki card visuals, and no mechanism/electron-flow tool, though that appears intentionally out of scope.

Maintenance

ActivityActive
ResponsivenessNo issues

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