captapi

youtube_shorts_comments

Comments on a YouTube Short — rejects long-form videos (≤3 min only). Costs 2 credits. Empty results and failures are never charged. Pass cache=true for a free 24h cache hit (default always fresh).

Input Schema

TableJSON Schema

Name	Required	Description
`url`	Yes	Public YouTube Shorts URL, e.g. https://youtube.com/shorts/ID (≤3 min). Long-form videos return HTTP 422 — use the matching /v1/youtube/… endpoint instead. The URL platform must match this endpoint's platform. Do not pass cross-platform URLs, e.g. YouTube to TikTok, Instagram to Facebook, LinkedIn to X/Twitter, or Pinterest to Rumble.
`cache`	No	Set true to serve from the 24h response cache (0 credits on hit). Default false — always fetch fresh.
`limit`	No	Max items to return (default 50, max 500). Flat 2 credits per call.
`cursor`	No	Pagination cursor. Leave empty for the first page; then pass the nextCursor value returned in the previous response.

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedSep 1, 2026

changedInput schema / properties / cache / description

Previous value: -"Set true to serve from the 24h response cache (0 credits on hit). Default false — always fetch fresh. Envelope includes cached + cachedAt on hits."New value: +"Set true to serve from the 24h response cache (0 credits on hit). Default false — always fetch fresh."

Changed3 schema fields changedAug 20, 2026

changedInput schema / properties / cache / description

Previous value: -"Set true to serve from the 24h response cache. Default false — always fetch fresh data."New value: +"Set true to serve from the 24h response cache (0 credits on hit). Default false — always fetch fresh. Envelope includes cached + cachedAt on hits."

changedInput schema / properties / limit / description

Previous value: -"Max items to return. Default 50, max 500. Billed per result."New value: +"Max items to return (default 50, max 500). Flat 2 credits per call."

changedInput schema / properties / url / description

Previous value: -"Public YouTube Shorts URL, e.g. https://youtube.com/shorts/ID (<=3 min). Long-form videos return HTTP 422. The URL platform must match this tool's platform. Do not pass cross-platform URLs, e.g. YouTube to TikTok, Instagram to Facebook, LinkedIn to X/Twitter, or Pinterest to Rumble."New value: +"Public YouTube Shorts URL, e.g. https://youtube.com/shorts/ID (≤3 min). Long-form videos return HTTP 422 — use the matching /v1/youtube/… endpoint instead. The URL platform must match this endpoint's platform. Do not pass cross-platform URLs, e.g. YouTube to TikTok, Instagram to Facebook, LinkedIn to X/Twitter, or Pinterest to Rumble."

Changed1 schema field changedAug 4, 2026

addedInput schema / properties / cursor

Added value: +{
+  "description": "Pagination cursor. Leave empty for the first page; then pass the nextCursor value returned in the previous response.",
+  "type": "string"
+}

Changed1 schema field changedAug 3, 2026

changedInput schema / properties / url / description

Previous value: -"Public YouTube Shorts URL, e.g. https://youtube.com/shorts/ID. Not a TikTok/Instagram/Facebook URL. The URL platform must match this tool's platform. Do not pass cross-platform URLs, e.g. YouTube to TikTok, Instagram to Facebook, LinkedIn to X/Twitter, or Pinterest to Rumble."New value: +"Public YouTube Shorts URL, e.g. https://youtube.com/shorts/ID (<=3 min). Long-form videos return HTTP 422. The URL platform must match this tool's platform. Do not pass cross-platform URLs, e.g. YouTube to TikTok, Instagram to Facebook, LinkedIn to X/Twitter, or Pinterest to Rumble."

Changed1 schema field changedJul 19, 2026

removedInput schema / properties / cursor

Removed value: -{
-  "description": "Pagination cursor. Leave empty for the first page; then pass the nextCursor value returned in the previous response.",
-  "type": "string"
-}

Changed1 schema field changedJul 18, 2026

addedInput schema / properties / cursor

Added value: +{
+  "description": "Pagination cursor. Leave empty for the first page; then pass the nextCursor value returned in the previous response.",
+  "type": "string"
+}

Changed1 schema field changedJul 16, 2026

changedInput schema / properties / cache / description

Previous value: -"Responses are cached for 24 hours by default. Set false to bypass the cache and always fetch fresh data (default true)."New value: +"Set true to serve from the 24h response cache. Default false — always fetch fresh data."

Changed1 schema field changedJul 15, 2026

addedInput schema / properties / cache

Added value: +{
+  "description": "Responses are cached for 24 hours by default. Set false to bypass the cache and always fetch fresh data (default true).",
+  "type": "boolean"
+}

Changed1 schema field changedJul 4, 2026

changedInput schema / properties / url / description

Previous value: -"Public YouTube Shorts URL, e.g. https://youtube.com/shorts/ID."New value: +"Public YouTube Shorts URL, e.g. https://youtube.com/shorts/ID. Not a TikTok/Instagram/Facebook URL. The URL platform must match this tool's platform. Do not pass cross-platform URLs, e.g. YouTube to TikTok, Instagram to Facebook, LinkedIn to X/Twitter, or Pinterest to Rumble."

First observedJun 7, 2026

TDQS

A4.1/5.0

Behavior4/5

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

With no annotations, the description carries the behavioral burden, and it does well: it discloses the 2-credit cost, no charge on empty results or failures, the 24h cache behavior, and the long-form rejection. It doesn't cover rate limits or auth, but the key operational edge cases for a read-only comments fetch are disclosed.

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?

The description is compact and front-loaded: the core scope constraint comes first, followed by cost and caching behavior. There is minor redundancy with the cache parameter's schema description, but the overall size is well controlled and no fluff is present.

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?

The tool has four parameters and no annotations or output schema, but the schema descriptions are rich and the top description adds cost, error behavior, and cache semantics. The only notable gap is the absence of any detail about the response shape beyond the cursor hint, which is not critical for selecting or invoking this tool.

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 100%, and the schema already documents defaults, max limit, pagination cursor behavior, URI format, and platform matching. The top description adds mostly cost and cache policy, which is useful but not parameter-specific. Since the schema handles parameter semantics fully, a baseline 3 is appropriate.

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 names a specific verb and resource: getting comments on a YouTube Short, with an explicit ≤3-minute constraint. It clearly distinguishes itself from generic YouTube comment tools by rejecting long-form videos, which is relevant given siblings like youtube_comments and youtube_comment_replies.

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

Usage Guidelines4/5

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

The description and url parameter give clear guidance: use for Shorts only, long-form returns HTTP 422 and should go to a /v1/youtube/… endpoint instead. The cache=true hint also tells agents when to use the cheaper path. It doesn't explicitly name the exact alternative endpoint, but the routing guidance is strong enough.

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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youtube_shorts_comments

Input Schema

Schema Changelog

TDQS

Glama MCP Gateway

Resources