Semantica is an open-source infrastructure layer that turns enterprise data into structured context and knowledge graphs, where ontologies define meaning and graph reasoning connects facts and decisions. It is intended for AI systems and agents that need traceable, governed, and explainable context in high-stakes domains. The catalogue add-ons provide agent workflows, hooks, and plugins for operating Semantica.
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 semantica-agi/semantica --skill reasongit clone --depth 1 https://github.com/semantica-agi/semanticaWrote 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/semantica-agi/semantica/reason)<a href="https://agentmods.dev/skills/semantica-agi/semantica/reason"><img src="https://agentmods.dev/badge/skills/semantica-agi/semantica/reason/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/semantica-agi/semantica/reason"><img src="https://agentmods.dev/badge/skills/semantica-agi/semantica/reason.svg" alt="Reviewed on agentmods" width="80" 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 139 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 | $0.00000 | $0.01329 |
| Opus 5 | $0.00000 | $0.00665 |
| Sonnet 5 | $0.00000 | $0.00266 |
| Haiku 4.5 | $0.00000 | $0.00133 |
Grade A, and why
reason scanned grade A with 0 findings 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 10d ago.
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.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 202 lines — stays where its author put it; the contents beside it link to each section on GitHub.
/semantica:reason
Apply reasoning over the knowledge graph. Usage: /semantica:reason <mode> [args]
$ARGUMENTS = reasoning mode + rules/observations/query.
deductive [--facts '<json-list>'] [--rules '<rule1>|<rule2>']
Apply deductive rules to known facts to derive new conclusions.
from semantica.reasoning.deductive_reasoner import DeductiveReasoner, Premise
reasoner = DeductiveReasoner()
# Add base facts to working memory
# Facts can be strings like "Person(John)" or structured dicts
import json
facts = json.loads(facts_json) if facts_json else []
reasoner.add_facts(facts)
# Apply logic with explicit premises
# Premise objects have: statement, confidence, source
premises = [
Premise(statement=fact, confidence=1.0)
for fact in facts
]
conclusions = reasoner.apply_logic(premises=premises)
Return: | Conclusion | Triggering Premises | Confidence | Rule Applied |
If zero rules given, run reasoner.prove_theorem() on any provided theorem:
proof = reasoner.prove_theorem(theorem=theorem_text)
Output: Proof: <proof.steps> | Valid: YES / NO
prove <theorem> [--facts '<json-list>']
Prove or disprove a theorem against known facts.
from semantica.reasoning.deductive_reasoner import DeductiveReasoner
reasoner = DeductiveReasoner()
import json
reasoner.add_facts(json.loads(facts_json) if facts_json else [])
proof = reasoner.prove_theorem(theorem=theorem)
Output:
Theorem: "<theorem>"
Result: PROVED ✓ | DISPROVED ✗ | UNDECIDABLE ⚠
Proof steps:
1. <premise> — <justification>
2. ...
→ QED: <theorem>
Confidence: <proof.confidence>
abductive <observation> [--knowledge '<json-list>'] [--top N]
Generate and rank hypotheses that explain an observation.
from semantica.reasoning.abductive_reasoner import (
AbductiveReasoner, Observation
)
reasoner = AbductiveReasoner()
import json
if knowledge_json:
reasoner.add_knowledge(json.loads(knowledge_json))
obs = Observation(description=observation)
# Generate all hypotheses then rank them
hypotheses = reasoner.generate_hypotheses(observations=[obs])
ranked = reasoner.rank_hypotheses(hypotheses)
best = reasoner.get_best_explanation(obs)
# Also get full explanations with evidence
explanations = reasoner.find_explanations(observations=[obs])
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.
- 10d ago First seen · 202 lines · 0 tokens per session scan A e523bca30770
reason is a skill published in the GitHub repository semantica-agi/semantica (12,474 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,329 tokens. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other skills, from other repositories
marimo-pair
Work inside the user's live marimo notebook from the code editor: run Python in the same kernel the user does, inspect live notebook state, and commit durable notebook changes through code mode. Use whenever you create, analyze, or improve the user's marimo notebook.
fill-model-descriptions
Fill missing and refresh obsolete model descriptions in packages/llm-info/data/models.yml by querying OpenRouter and provider documentation. Use when the user asks to populate model descriptions, enrich the model catalog, or curate descriptions after running pnpm sync-models.
create-atomic-context-provider
Build a BaseDynamicContextProvider that injects a named, titled block into an agent's system prompt at every run() — current time, user identity, retrieved RAG docs, session state, cached DB schema. Use when the user asks to "add a context provider", "inject X into the prompt", "give the agent dynamic context", "wire…
gsd-ai-integration-phase
Generate an AI-SPEC.md design contract for phases that involve building AI systems.
synalinks
Use for anything involving the Synalinks neuro-symbolic LM framework (Keras-inspired) — DataModel/Field/Input, JSON operators (+ & | ^ ), synalinks.ops, LanguageModel/EmbeddingModel and provider prefixes (openai/anthropic/ollama/groq/openrouter/bedrock/...); the Program class and its four building APIs…
prompt-lookup
Activates when the user asks about AI prompts, needs prompt templates, wants to search for prompts, or mentions prompts.chat. Use for discovering, retrieving, and improving prompts.