Pith Number

pith:HMVWYJAQ

pith:2026:HMVWYJAQUTOFK55DGA2FAEPBHY

not attested not anchored not stored refs pending

ToolSpec: Accelerating Tool Calling via Schema-Aware and Retrieval-Augmented Speculative Decoding

Cunxiao Du, Heming Xia, Mingbo Song, Wenjie Li, Yongqi Li

ToolSpec accelerates LLM tool calling up to 4.2 times by using tool schemas and past calls for accurate speculative drafts.

arxiv:2604.13519 v2 · 2026-04-15 · cs.CL

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\usepackage{pith}
\pithnumber{HMVWYJAQUTOFK55DGA2FAEPBHY}

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Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Claims

C1strongest claim

ToolSpec achieves up to a 4.2x speedup, substantially outperforming existing training-free speculative decoding methods.

C2weakest assumption

Tool-calling traces are highly structured, conform to constrained schemas, and often exhibit recurring invocation patterns that can be exploited for accurate draft generation.

C3one line summary

ToolSpec accelerates LLM tool calling by up to 4.2x via schema-aware finite-state machine drafting and retrieval of similar past invocations.

Cited by

1 paper in Pith

Ghost Tool Calls: Issue-Time Privacy for Speculative Agent Tools

Receipt and verification

First computed	2026-05-29T01:05:09.800715Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

3b2b6c2410a4dc5577a330345011e13e0ce86ffec626c2749bc4f32707ff4856

Aliases

arxiv: 2604.13519 · arxiv_version: 2604.13519v2 · doi: 10.48550/arxiv.2604.13519 · pith_short_12: HMVWYJAQUTOF · pith_short_16: HMVWYJAQUTOFK55D · pith_short_8: HMVWYJAQ

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/HMVWYJAQUTOFK55DGA2FAEPBHY \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: 3b2b6c2410a4dc5577a330345011e13e0ce86ffec626c2749bc4f32707ff4856

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "7583a852c4ce65075affcfa8f9326141373c1cb82145c15065b021a4f373098e",
    "cross_cats_sorted": [],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.CL",
    "submitted_at": "2026-04-15T06:05:11Z",
    "title_canon_sha256": "2c6ec7183739b2bddb5024a79df32a78fcd014ad84a21dcd8ba7001d713652f5"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2604.13519",
    "kind": "arxiv",
    "version": 2
  }
}