fetch

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, but the description adds substantial behavior beyond that: default page count, default character count, max_chars bounds, the 50-page limit, continuation guidance, and the auto-selection caveat for parent Zotero items. This is rich, useful context.

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?

Four dense sentences, each adding distinct value: purpose, defaults and limits, continuation guidance, and an important caveat. The most identifying information is front-loaded and there is no filler or repetition of the schema.

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?

An output schema exists, so return values do not need explanation. The description covers core behavior, constraints, and an important sibling alternative. The only real gap is the underspecified offset and expected_sha256 semantics, but defaults make the tool callable without those details.

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 does clarify the ID scheme, max_chars range and default, page-selection limits, and the importance of retaining expected_sha256. However, offset and the exact meaning of expected_sha256 are not fully explained, so it is strong but not complete.

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 and resource: 'Read a source excerpt by file:, zotero:, project: or feedback: ID.' This clearly distinguishes it from siblings like list_files, search, and read_page_image, and names the ID formats it accepts.

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?

It gives explicit routing guidance: 'Use get_writing_context for project IDs.' It also provides operational guidance about continuing only as needed and retaining page range and expected_sha256. It does not explicitly state when to prefer fetch over siblings, but the purpose distinction is strong enough.

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