telegram_download_mediaDownload a Telegram message attachment to the local media directory and return its path and size. Limit file size with an environment variable to avoid large transfers.
Download the attachment of a message to the local media directory. Returns local path + size. Set TELEGRAM_MAX_DOWNLOAD_BYTES in env for a cap (0 = unlimited).
| Name | Required | Description | Default |
|---|---|---|---|
| chat | Yes | ||
| fileName | No | ||
| messageId | Yes |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Adds real context beyond the annotations: it discloses the destination directory, the return shape (local path + size), and the TELEGRAM_MAX_DOWNLOAD_BYTES env cap including the 0 = unlimited edge case. However it doesn't cover overwrite behavior for existing files, what happens when the cap is exceeded, or auth requirements.
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 core action, then the return value, then the env cap detail. No 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?
There is no output schema, and the description compensates by stating the return values. Still incomplete for a write-to-disk tool: file naming/overwrite rules, error cases, and parameter meanings are 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 0%, so all three parameters (chat, messageId, optional fileName) rely on the description, which says nothing about them. Only a weak implication that fileName relates to the attachment's saved name.
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: downloading a message attachment to the local media directory. It is clearly distinguishable from siblings like telegram_list_downloads and telegram_delete_download, though it never names them.
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?
No guidance on when to use this versus list_downloads/delete_download, nor on prerequisites such as the message actually having an attachment. Usage must be inferred entirely from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.