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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the selection-by-two-IDs behavior but provides no details about error cases, such as what happens when the chunk is not found, or whether the full chunk content is returned. No contradiction with annotations.

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 a single sentence with no filler, and the verb and required identifiers are front-loaded. Every word contributes to the meaning.

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 simple read-only fetch with two required string parameters and no output schema, the description states the operation and required inputs. It does not specify the response structure or chunk content, but the low complexity and clear title make this an acceptable level of completeness.

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. It only restates the parameter names in prose ('by document_id and chunk_id') without explaining what a chunk is, the format of the IDs, or how they relate. This adds minimal semantic value beyond 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?

The description uses a specific verb 'Retrieve' and names the resource 'specific chunk', with explicit identifiers (document_id and chunk_id) that define the operation's scope. It is clearly distinct from sibling tools like semantic_search or list_media, which have different purposes.

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 usage context is implied: an agent would use this tool when it already has both a document_id and a chunk_id. However, there is no explicit when-to-use guidance or mention of alternatives, so the agent must infer the appropriate invocation scenario.

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