httpx_probe

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

No annotations are present, so the description must carry the burden of behavioral context. It discloses that it uses the ProjectDiscovery httpx CLI (not the Python library), has a threads parameter with max 200, and requires the target to be in tengu.toml allowed_hosts. It also states return output includes status codes, titles, and detected technologies. This goes beyond the schema, though it could be more explicit about network side effects.

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?

The description is well-structured with a summary, argument list, returns, and notes. It is front-loaded with purpose and contains no filler—each line provides value, including the note distinguishing from the Python httpx library.

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 description is complete for a tool with an output schema: it covers purpose, all parameters, output highlights, and a critical configuration constraint. The minor ambiguity of 'host or URL list' in the opening line is clarified in the Args section with 'Target URL or host.'

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?

All four parameters are described in the Args section: target with an example, threads with default and max, detect_tech with default, and timeout as an override. This fully compensates for the 0% schema description coverage, adding meaning well beyond type and default.

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 opens with 'Probe HTTP services on a host or URL list using ProjectDiscovery httpx,' which uses a specific verb (probe) and resource (HTTP services). It further details capabilities like technology detection, status code enumeration, and title extraction, making it distinct from siblings like nmap_scan (network scanning) or katana_crawl (web crawling).

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 a clear use case: 'Useful for quickly triaging large host lists after subdomain enumeration.' This implicitly tells the agent when to select this tool over others, though it does not explicitly state alternatives or exclusions. The note about allowed_hosts also gives context for when it can be used.

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