probe_sources

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

With no annotations supplied, the description carries the full burden and does disclose the key trait: it actually fires real requests rather than returning cached capability data. It also enumerates the possible outcomes (ok / blocked / needs_key / error) with real HTTP codes, which tells the agent to expect partial failure and to branch on 'needs_key'. It omits cost/latency, rate limits, and whether repeated calls are safe.

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 what it does, then the return shape, then the usage directive. The status enumeration partially duplicates the output schema, but it is short enough that the overlap costs little.

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?

An output schema exists and the description correctly avoids re-explaining return values in depth while still naming the status taxonomy. For a zero-parameter preflight tool with no annotations, the remaining gaps (latency, whether probing is expensive, idempotence) are minor but would help an agent decide how often to call it.

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?

The tool takes zero parameters, so there is no parameter semantics to add; baseline 4 applies. Nothing in the description misleads about inputs.

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 — probe all data sources for real-time availability — and scopes it to the entire source set rather than one source. The added line '先跑这个' positions it in the workflow relative to the manual_* siblings, so an agent can tell it is a preflight check rather than a query.

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?

Explicit ordering guidance ('run this first') plus the decision it enables — what can be queried now versus what must be escalated to manual — gives clear when-to-use context and implicitly points at the manual_* siblings. It does not state when this tool should be skipped (e.g. a fresh probe already done), so it stops short of full when/when-not coverage.

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