crypto_download_url

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

With no annotations, the description must disclose behavior. It mentions encryption/decryption but does not clarify how the 'action' parameter (encrypt/decode) interacts with the input. The phrasing '输入普通 http(s) 地址或对应前缀的密文' suggests auto-detection, yet the schema requires an explicit action, creating ambiguity.

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 concise sentences, front-loaded with the primary purpose. Every word is informative, and there is no redundancy or filler.

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?

The tool has 3 parameters (one required, two with enums), no output schema, and no annotations. The description covers the core purpose but omits how the action parameter affects behavior, what output is returned, and default behaviors. It is insufficiently complete for an agent to invoke correctly without further inference.

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 must compensate. It indirectly explains 'text' (URL or ciphertext) and 'engine' (via the listed prefixes), but it doesn't mention the 'action' parameter or map it to encrypt/decode. Partial compensation, but incomplete.

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?

The description clearly states the tool's function: '下载地址加解密' (download URL encryption/decryption), and specifies the supported protocols (thunder, flashget, qqdl). This distinguishes it from generic crypto/encoding siblings like crypto_symmetric or encode_base64.

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 description provides clear context: it is for download URLs and inputs can be plain http(s) addresses or ciphertext with the listed prefixes. It does not explicitly name alternatives or exclusion cases, but the specific scope is evident from the context.

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