Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add Laboratoire-de-Chemoinformatique/SynPlanner --skill synplanner-usagegit clone --depth 1 https://github.com/Laboratoire-de-Chemoinformatique/SynPlannerWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/laboratoire-de-chemoinformatique/synplanner/synplanner-usage)<a href="https://agentmods.dev/skills/laboratoire-de-chemoinformatique/synplanner/synplanner-usage"><img src="https://agentmods.dev/badge/skills/laboratoire-de-chemoinformatique/synplanner/synplanner-usage.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high System Prompt Leakage · line 182 Skill contains instructions that could directly expose system prompts, internal rules, or hidden instructions to users or external parties.Fix: Remove any instructions that reveal, print, or output system prompts or internal rules. System instructions should never be exposed to end users.
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00182 | $0.03213 |
| Opus 5 | $0.00091 | $0.01606 |
| Sonnet 5 | $0.00036 | $0.00643 |
| Haiku 4.5 | $0.00018 | $0.00321 |
Grade A, and why
synplanner-usage scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured today.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
curl -O https://raw.githubusercontent.com/Laboratoire-de-Chemoinformatique/SynPlanner/main/configs/planning_standard.yaml How it starts
The opening of the file, as written. The whole thing — 288 lines — stays where its author put it; the contents beside it link to each section on GitHub.
SynPlanner usage
READ references/tasks.md FIRST
Before exploring the repository, before grepping the source, before writing a
line of code — read references/tasks.md, sitting next to this file.
It maps around thirty tasks to the exact API pieces each one needs, in order, with links to a worked notebook and the reference page. This file gives the rules. That one gives the sequences, and no sequence is repeated here.
Skipping it means reconstructing from the source what is already written down — which is where the time goes, and where wrong answers come from. Read it first even when the task looks simple.
What SynPlanner is
SynPlanner is a high-level reaction processing toolbox for retrosynthesis. It orchestrates chython-synplan (also known as chython, formerly CGRtools) — a pure-Python chemoinformatics engine with capabilities comparable to RDKit — for reaction data curation, retrosynthetic planning, and analysis of synthetic routes.
When to use something else
SynPlanner is for retrosynthesis and reaction-level work. It does not need to be in the loop for plain molecule handling.
chython is already installed as SynPlanner's engine and covers most of what RDKit
does. For molecule-level work that never touches a reaction or a route, use
from chython import ... directly rather than going through SynPlanner. Do not
reach for RDKit just because the task looks like ordinary cheminformatics — chython
is already there.
Use RDKit only where chython genuinely lacks the capability. SynPlanner itself does
exactly this for synthetic-accessibility scoring and molecular descriptors — see
synplan/chem/rdkit_utils.py.
Do not overcorrect. "Prefer chython" is not "never RDKit" — when chython does not have the function, reach for RDKit and say so, rather than hand-rolling it.
A library is not a route
synplan.chem.synthon is a port of Synt-On and answers a different question from
planning: what can be built from a catalogue, not how to make one molecule. Asked
for a synthesis, plan. Asked for a library, for analogues, or for what a catalogue
reaches, fragment and enumerate. Do not reach for Tree to enumerate, and do not
hand back a fragmentation pathway as a route — it names no reaction and no
conditions.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- today Changed · +9 lines 8bb2410826c4
- 8d ago First seen · 279 lines · 182 tokens per session scan A 3ce01890878d
synplanner-usage is a skill published in the GitHub repository Laboratoire-de-Chemoinformatique/SynPlanner (59 stars, last pushed today), licensed MIT. It adds 182 tokens to every session and 3,213 once invoked, about $0.0009 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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