Expand a search hit into surrounding context

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 structurally. The description usefully discloses that it returns contiguous surrounding chunks rather than isolated fragments, but says nothing about budget truncation behavior (maxChars), pagination, or size limits.

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 tight sentences: purpose and addressing first, then the usage trigger. No filler, and the key routing information is front-loaded.

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?

For a read-only expander with full schema coverage and annotations carrying the safety profile, the description covers what it returns and when to use it. It lacks output-format/pagination detail, but with no output schema that gap is minor.

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 coverage is 100%, so baseline is 3. The description meaningfully adds that the hit can be addressed either by chunk_id OR by document_id + ordinal, which the schema lists as independent optional fields without stating they are alternative addressing modes.

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 (Return) and resource (contiguous chunks around a search hit) and clarifies the value: reading a whole function/section. It is clearly distinguishable from siblings like search (which finds fragments) and get_chunk.

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?

"Use after `search` when a result looks cut off" gives a clear trigger condition and sequences it relative to a sibling. It stops short of explicitly naming alternatives (e.g., get_chunk) or when not to use it, so it is not a full 5.

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