read

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

No annotations are provided, so the description carries the full burden, and it does disclose meaningful behavior: fetch-and-store idempotency ('no fetch if already stored'), section-selection around the goal, EvidenceEntry production with hit offsets, the max_chars range, and a hard refusal for unsearched URLs. It stops short of stating storage/auth details or error behavior beyond the refusal.

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 dense sentences, front-loaded with the core action before the mechanics, and every clause carries operational information (fetch caching, section selection, hit offsets, max_chars bounds, URL gate). It is slightly packed but not padded.

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?

With an output schema present, the description needn't describe return shapes, and it appropriately focuses on the preconditions and side effects of the read. Given three parameters and a gated workflow, it covers the essential context an agent needs to invoke this correctly, with only minor gaps around URL/goal formatting.

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 and does: max_chars gets a stated purpose and bounds (500–20000), goal gets its role as the relevance axis for section selection, and url gets the implicit constraint that it must originate from a prior search. This adds real meaning beyond bare types, though it doesn't specify url/goal formats.

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+resource ('Read a discovered source against a goal and capture citable evidence') and distinguishes itself from siblings by naming the gate ('Refuses any URL not returned by a prior search') and by hinting at the search/read pipeline. An agent can tell this apart from search, grep, and open.

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 implies the workflow constraint (must follow a prior search in this session) which is effectively a precondition and an exclusion, and the goal parameter indicates the usage mode. However it never names an explicit alternative for cases where the URL wasn't from search, so it's clear context but not a full when/when-not/alternatives rubric.

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