fetch_source

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

With no annotations, the description carries the full burden. It does disclose the meaningful side effects: it creates a run directory, downloads audio, and pulls metadata plus Vietnamese subtitles when available, and it returns run_dir. It says nothing about network/auth requirements, what happens on an invalid YouTube link or unsupported file, or whether re-running overwrites an existing run folder.

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 sentences, front-loaded with the core action and the input variants, then the return value, then the optional flag's tradeoff. Dense but every sentence adds information; only the parenthetical extension list is slightly padded.

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?

An output schema exists, so run_dir need not be explained in depth, and the workflow position ('dùng cho các tool sau') is covered. Still, for a network-touching tool that writes a new run folder, the unexplained 'title' parameter and the absence of any failure or overwrite behavior leave real gaps.

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 0%, so the description has to compensate. It explains 'source' well (YouTube URL vs. local .mp3/.m4a/.wav and .vtt/.srt/.txt/.md paths) and gives the semantics of with_audio=false. The third parameter, 'title', is never mentioned, leaving one of three parameters undocumented in both schema and description.

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 artifact: 'Tạo thư mục run mới' (create a new run folder), and enumerates precisely what it ingests – a YouTube link or a local audio/subtitle/transcript file. An agent immediately knows this is the entry point that materializes a run workspace, which is distinct from siblings like list_runs, transcribe, or run_status.

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 a clear conditional: with_audio=false when you only need metadata plus subtitles and are confident the subtitles are good enough. It also tells the agent this must happen before 'các tool sau' (subsequent tools). It does not name an explicit alternative tool or state exclusions, so it stops short of a 5.

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