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 real behavioral context beyond them: the output is decoded as UTF-8 text, there is a size limit with a stated default of 512 KB, and oversized files are rejected rather than truncated—an important failure mode. It does not mention authentication or permission requirements for the connection.

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 compact sentences, front-loaded with the core action and output format, followed by applicability and then the size constraint with its remedy. No redundant restatement of the tool name or filler wording.

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 tool with no output schema, the description adequately covers the return type (UTF-8 text) and the size-limit behavior. However, with six parameters at 0% schema coverage and a non-obvious overlap between key/name/path, the definition leaves an agent without enough guidance to construct a correct call.

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% across six parameters, so the description must carry the burden, but it only explains max_kb and its default. The ambiguity between key, name, path, and mime_type, plus what connection_id selects, is left entirely undocumented—an agent cannot tell which identifier fields are needed or how they interact.

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 a file and return its contents as UTF-8 text, scoped to text files such as configs, notes, and logs. It also implicitly distinguishes itself from get_download_url, which it names for the oversized case, so an agent can pick between them 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?

Gives explicit use conditions (text files: configs, notes, logs), an explicit exclusion with the reason (files above max_kb are rejected), a pre-check recommendation (verify size via list_files), and the named alternative (get_download_url). Little is left to inference.

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