MCPTube

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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds genuinely new context beyond that: the call consumes no quota (a cost/rate consideration the annotations don't express) and that the response includes upcoming reset timing, which tells the agent what state it will observe.

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 sentences, no filler, with the core return content front-loaded and the practical "Uses no quota" caveat placed last where it reads as a call-time note. Nothing is redundant with the title or annotations.

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 carries the burden of describing returns and does so at a useful level: plan, applicable counters, and next reset. It stops short of detailing the shape of the counters (per-feature, units, limits vs. consumed), which would fully close the gap for a zero-param reporting tool.

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 there is nothing for the description to disambiguate—the baseline of 4 applies. The description correctly implies the call is scoped implicitly to the authenticated account rather than requiring any selector input.

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 ("Returns") and specific resources (the account's current plan and applicable usage counters, plus their reset timing). The sibling tools are all video-related, so this account/usage tool is unmistakably distinct without needing to name an alternative.

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?

"Uses no quota" strongly implies this is free to call at any time, which is meaningful invocation guidance for a quota-checking tool. However, it never states when an agent should reach for this versus other account/state checks, and there is no explicit exclusion or alternative named; usage is implied rather than directed.

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 readOnly, idempotent and non-destructive, so the safety profile is covered. The description adds a genuinely non-obvious operational fact — it does not consume the daily call quota — which is exactly the kind of quota/cost context annotations cannot express.

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, front-loaded with the return contents, followed by the two constraints. No filler, though the trailing quota sentence could be merged to tighten further.

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?

No output schema exists, and the description compensates by naming the returned fields (channel, duration, chapters, subtitles) plus the metadata-only and quota traits. An agent has enough to decide and call correctly.

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% and the single parameter's description already lists all accepted URL forms (watch, youtu.be, shorts, live, embed, clip). The description adds nothing about the parameter, so the 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 and resource ("Returns information about a YouTube video") and enumerates the fields returned. The "metadata only" clause implicitly separates it from transcribe_video, but no sibling is named explicitly.

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 implied: use it to inspect a video without fetching a transcript. There is no explicit when-to-use/when-not guidance and no mention of search_videos, transcribe_video, or get_usage as alternatives.

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 readOnly, idempotent, non-destructive, open-world. The description adds that results include titles, channels, durations and links, and that pagination is supported — useful beyond annotations. But it doesn't mention rate limits, quota, or how the cursor relates to result stability (that's only in the schema).

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 and then the return fields and pagination. Zero waste.

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 read-only search tool with full schema coverage and rich annotations, this is nearly complete. Minor gap: no explicit guidance on when to prefer this over get_video_info rather than direct ID lookup, but nothing critical is missing.

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 the baseline is 3. The description mentions pagination, nodding at the cursor param, but adds no syntax or format detail beyond what the schema already documents for query, cursor, region, and language.

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 (searches/finds) and resource (YouTube videos) plus the fields returned. Clearly distinguishable from siblings like get_video_info and transcribe_video which operate on a single known video.

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 query-based discovery nature implies when to use it versus get_video_info, but the description never explicitly says 'use this to find videos when you don't have an ID' or mentions alternatives. Pagination behavior is mentioned, which gives some operational context.

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 readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds the return formats (SRT and plain text), which annotations cannot express, but it omits notable behavior like what happens when captions are missing and that forceAiTranscription is plan-limited—though the schema hints at the latter.

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?

A single front-loaded sentence with no wasted words. It is efficiently sized, though its brevity leans toward under-specification rather than complete economy.

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 must convey the return shape; stating SRT and plain text partially does this. However, for a transcription tool subject to plan limits and possible missing captions, it leaves behavioral gaps an agent may need.

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 all four parameters including the format enum, language, and forceAiTranscription limits are fully documented in the schema. The description only echoes the dual-format return and adds no syntax or language/fallback detail beyond the schema, making baseline 3 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 (Returns the transcription) and resource (a YouTube video) plus the output formats. It implicitly distinguishes it from get_video_info (metadata) but never names any sibling, so differentiation is inferred rather than stated.

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?

There is no guidance on when to use this over get_video_info or search_videos, and no mention of prerequisites or alternatives. The agent must infer usage from the name alone.

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