Download Telegram media by t.me link

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

With no annotations, the description carries the full behavioral burden. It does disclose two useful traits — it returns absolute paths of newly downloaded files and skips already-present files (--skip-same) — which is real idempotency information. But it says nothing about authentication/prerequisites for Telegram access, partial-failure behavior, or whether downloads are network-bound, leaving meaningful gaps.

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, no filler; the core action and return value come first and the routing hint and skip behavior follow in priority order. Every sentence 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?

With a fully described schema and no output schema, the definition covers the essentials: what it downloads, from what input, and what it returns. It falls short only on prerequisites (auth/session) and failure behavior for what is a file-writing, network-dependent operation.

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 dest, urls, and extensions are already fully documented in the schema, including the https://t.me/ prefix requirement. The description adds no extra semantics about these parameters, 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 ('Download the media of specific Telegram messages given their t.me links') and pins the input form with a concrete example URL. The clause 'rather than a chat to scan' implicitly separates it from the chat-scanning sibling tg_download, so an agent can route without opening schemas.

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 an explicit selection condition: 'Use when you already have message links rather than a chat to scan.' That clearly signals when this tool applies and implies the alternative (bulk chat scanning) is a different tool, though it never names tg_download explicitly.

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