FreqBlog Music Metadata

Get Audio Features (Batch)

get_audio_features_batch

Read-only

Get audio features for MANY tracks in one call (up to 50 processed) — ideal for analysing a whole playlist at once. Identify each item by name (track/artist), by isrc (matched exactly first — best for CJK / K-pop / niche tracks whose fuzzy name-match misses), or both (ISRC first, name as the fallback).

One bad entry never fails the batch. Items beyond the 50-per-call cap come back with
`found: false` and `backfill_status: "over_limit"`; an item missing BOTH `track` and
`isrc` comes back `"invalid_no_query"`. Neither is processed or charged — the response's
`skipped` field counts them, so split a long list into calls of <=50 and resubmit any
skipped rows.

Returns counts (`found` / `not_found` / `skipped`) plus a per-track `results` array, where
each entry's `result` is the same feature object as get_audio_features (or null when not
found), and `isrc` is echoed back. An item is billed only when it returns features or
queues an on-demand ingest; an ISRC/name with no match anywhere is free. For a single
track, use get_audio_features.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`tracks`	Yes	List of {track?, artist?, isrc?} objects. Up to 50 are processed per call; any extra (up to 200 accepted) come back skipped. Each item should carry `track` or `isrc`.

Output Schema

TableJSON Schema

Name	Required	Description	Default
No arguments

TDQS

A4.9/5.0

Behavior5/5

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

Beyond annotations (readOnlyHint, openWorldHint), the description discloses critical behavioral traits: how bad entries are handled, billing conditions, return structure, and special statuses like invalid_no_query and over_limit. No contradiction with annotations.

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?

Well-structured with front-loaded main purpose, followed by clear details in separate paragraphs. Every sentence adds value, though slightly verbose in explaining ISRC behavior, making it not perfectly concise.

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?

Despite having an output schema (not shown), the description thoroughly describes return values: counts, per-track result array, feature object same as get_audio_features, skipped items with reasons, and billing info. Completely covers what an agent needs to understand the tool's behavior.

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 coverage is 100%, but description adds significant meaning: explains the relationship between isrc and track (exact match first, fallback), optional artist for accuracy, and consequences of missing both. This enriches the schema beyond its own descriptions.

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 clearly states it retrieves audio features for many tracks in one call, ideal for analyzing playlists, and explicitly distinguishes from sibling get_audio_features by recommending that tool for single tracks.

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 advises when to use (batch of up to 50 tracks) and when not (single track, use get_audio_features). Details such as ISRC exact matching, no batch failure on bad entries, and instructions for handling over-limit items provide clear usage guidance.

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

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TDQS

A4.6/5.0

Disambiguation5/5

Each tool has a clearly distinct purpose: search, feature retrieval, set building, transition scoring, etc. There is no overlap or ambiguity.

Naming Consistency5/5

All tools use consistent snake_case verb_noun pattern (e.g., find_tracks_by_key, get_audio_features, build_setlist). No style mixing.

Tool Count5/5

12 tools is well within the ideal range, covering search, features, discovery, and set building without bloat or deficiency.

Completeness4/5

Core metadata retrieval, search, harmonic mixing, and DJ set tools are all present. Minor gaps like user library management are outside the scope.

Resources

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