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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds genuinely non-obvious behavior: value is returned one page at a time, and reading a large value is costly enough that est_tokens should be checked and the handle narrowed first. It does not cover error behavior for an invalid handle, so not a 5.

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 sentences, zero filler; the verb and resource are front-loaded and the second sentence carries a concrete cost-saving heuristic. 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?

With annotations covering the safety profile, a full output schema, and 100% parameter coverage, the description only needs to supply workflow and cost context, which it does. Nothing required to invoke this correctly is missing from the combined definition.

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% and the schema already documents view, limit and offset semantics in detail, so the baseline is 3. The description reinforces the view modes and paging but adds no syntax or format detail beyond what the schema provides.

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 concrete verb and resource ('Look at a handle') and enumerates the three modes it supports (summary, value, provenance), which no sibling tool (discover, invoke, run_pipeline, etc.) covers. An agent can distinguish this as the read/inspection tool for an existing handle without opening the 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?

Gives a clear conditional workflow: check est_tokens in the summary before reading a big value, and narrow with an op first (explicitly naming find, select, filter, fit) because it is usually cheaper. It stops short of naming which sibling tool to pick when several could apply, so it is strong context guidance rather than explicit tool-selection routing.

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