Read a stored result

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

Annotations already cover the safety profile (readOnly, idempotent, closed-world), so the description is free to add the non-obvious behavior: offset/limit measure characters for answer/content but items for lists, and next_offset should be followed to continue. These are genuine execution-level details an agent would otherwise get wrong. It stops short of covering truncation via max_bytes or what happens on an unknown/expired result_id.

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?

Front-loaded with the core action, then two compact field inventories and a one-line pagination rule. Dense and waste-free, though the field lists partly restate what the output schema already exposes.

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 return shape doesn't need re-explaining, and the pagination contract — the tool's real complexity — is covered. Gaps remain around max_bytes truncation behavior and how result_id is obtained, which matter for a 5-parameter tool.

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 only 20%, so the description must compensate, and it does so partially: it defines offset/limit units and enumerates valid values for fields per result type. However, max_bytes (a truncation control with 512–16384 bounds) and the meaning/format of result_id are left entirely to the schema.

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 ('Page through a stored search or fetch result') and immediately distinguishes itself from the sibling producer tools with 'without calling any provider.' An agent can tell this apart from search/fetch/health without opening a schema.

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 phrase 'without calling any provider' implies the intended context (re-reading an already-produced result rather than issuing a new search/fetch), but the description never names search or fetch as the source of a result_id, nor states any exclusion or prerequisite. Usage is inferable but not spelled out.

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