TranscriptYT

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

Annotations only cover readOnlyHint and openWorldHint, so the description carries useful extra weight: it discloses the credit cost on success and the AI-transcription fallback cost (1 credit per started minute) for videos without captions. It stops short of describing error behavior, rate limits, or partial-failure semantics.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Four tight sentences, front-loaded with purpose, then input forms, then format guidance, then cost. Every sentence adds information an agent needs; nothing is redundant with the schema.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 10-parameter tool with no output schema, the description covers what the output looks like (title + text in Markdown, timestamped segments in json, subtitle files) and the cost model. The remaining mode/format nuance is fully handled by the schema's parameter descriptions, so this is close to complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% (baseline 3), and the description genuinely adds beyond it: the "full URL or 11-character video ID" detail sharpens the url field, the default format is explained as the most compact reading option, and json/srt/vtt are tied to concrete use cases (timestamped segments, subtitle files).

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ("Fetch the transcript of a public YouTube video") plus an important scope constraint (public videos only). The verb/noun pair is clearly distinct from siblings like summarize_video or search_youtube, but the description never names a sibling to sharpen the boundary.

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

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

Gives real selection guidance for the format parameter: Markdown is called out as the default and "most compact format for reading or summarizing," with json for timestamped segments and srt/vtt for subtitle files. It does not, however, say when to choose this tool over summarize_video or search_youtube.

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

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds two useful bits beyond the schema - that the result is keyed to the current API key and that the call costs nothing - but says nothing about rate limits, error behavior, or freshness of the credit figure.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences with zero filler; the resource and the cost caveat are both front-loaded and every word earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a parameterless, read-only status tool with no output schema, the description names the returned entities (remaining credits and plan) and the credential scope, which is enough to call it correctly. It could say a bit more about what happens when the key is invalid, but the essentials are present.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so the baseline is 4. The description correctly adds no parameter detail, since there is nothing to parameterize.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (Show) and resource (remaining credits and plan) scoped to 'this API key', so an agent immediately knows what it returns. It does not name or contrast sibling tools, though get_transcript and list_languages operate on entirely different resources so confusion is unlikely.

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

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

Usage is only implied - the 'Free' tag hints this is a cheap pre-flight check, but the description never states when to call it (e.g., before consuming credits) or any alternative. Adequate but no explicit when/when-not guidance.

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

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and network profile is covered. The description adds genuinely useful non-obvious context: the operation is free and consumes no credits, which matters for budgeting against sibling tools. It does not contradict annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, front-loaded with the core purpose followed by the cost note. No filler or redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter read-only listing tool with annotations covering safety and no output schema to document, the description is essentially complete. The only mild gap is lack of return-format guidance, though that is arguably acceptable given the simple, self-explanatory output.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the single 'url' parameter documented as 'YouTube URL or video ID'. The description adds no format or syntax detail beyond that, so the baseline 3 applies when the schema fully carries parameter documentation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (List) and resource (caption tracks/languages) tied explicitly to a YouTube video. Clear enough that an agent can distinguish this listing operation from get_transcript and get_usage without opening the schema.

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

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

The description implies usage (enumerate available caption tracks for a video) and the 'Free, and does not use credits' note hints at when to prefer it over credit-consuming siblings. However, it never explicitly names alternatives like get_transcript or explains when to choose one over the other.

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

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description goes beyond them by disclosing result ordering ('newest first'), the returned fields (titles, durations), and that the call is free — meaningful traits not present in the structured fields.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences, zero waste, with the core behavior and accepted inputs front-loaded before the follow-up routing hint.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description usefully states what comes back (titles and durations) and the sort order. The only minor gap is that it does not mention the default/ max limit behavior for paging through large playlists.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so both parameters are already documented in the schema. The description's mention of accepted input formats ('playlist links or IDs and channel links or @handles') largely restates the url schema description, and it says nothing about the limit parameter — the baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource and covers both modes (playlist videos or channel uploads) with scope detail ('newest first', 'titles and durations'). An agent can immediately distinguish this from get_transcript, which the description names separately.

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

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

Gives clear context ('Free') and explicitly routes the agent forward: 'Use get_transcript on the videos you need.' It does not state when-not to use it or contrast against list_languages/get_usage, but the usage intent is unambiguous.

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

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered; the description adds genuinely new behavioral facts — that the call is free and exactly which fields are returned (IDs, titles, channels, durations, view counts). It omits pagination/limit behavior and any rate-limit notes, keeping it below a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three tight sentences: scope first, return shape second, cost and next-step routing last. No filler, no repetition of the title, and the most decision-relevant information is front-loaded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description usefully enumerates the returned fields and flags the tool as free, which is exactly what an agent needs to chain into get_transcript. Only minor operational details (result ordering, how limit interacts with channel search) are left unstated.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so query, limit, and channel are already fully documented in the schema. The description restates the channel-accepts-link-or-@handle detail that the schema also carries, adding no syntax or format information beyond it. Baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (search) plus resource (YouTube videos) and additionally defines the channel-scoped variant, which no sibling covers. An agent can distinguish it from get_transcript, list_playlist_videos, and the other siblings without opening any schema.

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

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

"Use get_transcript on the videos you need" gives an explicit follow-on routing instruction, and the channel parameter is described as an alternate search mode. It stops short of stating when NOT to use this tool (e.g. versus playlist enumeration), so it is clear context rather than full when/when-not guidance.

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

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

Goes well beyond the readOnlyHint and openWorldHint annotations by disclosing the credit cost model (1+1=2, with long videos costing ~1 more per 45 minutes), the language behavior, and the transcript dependency. This is exactly the kind of operational context annotations cannot carry.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three tight sentences: purpose, language semantics, then cost. Front-loaded with the primary value proposition, no filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Comprehensive for a 3-param read tool: it covers outputs, language handling, and cost. No output schema exists, but the description enumerates the deliverables. Minor gap: doesn't address failure modes (private/no-caption videos) despite the 'public' qualifier implying them.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds meaning: it clarifies that translate_to changes which transcript is summarized (not just output language) and that output language follows the transcript. This exceeds what the schema field descriptions convey.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (summarize) and resource (YouTube video) and enumerates the outputs (summary, key points, timestamped study notes). This clearly distinguishes it from the sibling get_transcript.

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

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

Implies usage context: it operates on public YouTube videos and generates summaries from transcripts. The relationship to get_transcript is implied (this summarizes, that just fetches), but there are no explicit when-to-use/when-not statements or named alternatives.

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