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 a meaningful trait: this 'get' tool mutates the store by writing processed results back, and auto=false suppresses that. It says nothing about permissions, rate limits, or failure behavior when a URL cannot be processed, so the disclosure is partial.

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 tight sentences with no filler, and the core retrieval scope is front-loaded before the cache-miss caveat. Slightly terse for the amount of conditional logic it encodes, but every clause 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?

No output schema and no annotations, with six parameters and non-trivial fallback logic. The description covers the main retrieval plus write-back behavior, but leaves unclear what '来源与时间' looks like, how q/id/url interact, and what happens on a failed fetch — gaps the schema does not fill either.

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 the baseline is 3. The description only echoes the url/auto behavior already documented in the schema and adds no precedence rules (q vs id vs url) or format guidance for max_chars/kind.

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 (取/retrieve) and resource (公共仓库里的成品 with source and time), and the second sentence clarifies it is a cache-with-fallback retriever. It distinguishes itself implicitly from shelf_find/shelf_put, but never names a sibling, and '成品' stays vague about what the stored artifact actually is.

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 explains the cache-miss path (URL given and not in store → process and write back), which implies when the tool is useful. But it gives no explicit routing: nothing says to call shelf_find first to obtain an id, or when to prefer web_read over this cached variant, so the agent must infer the workflow.

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