DPLA — Browse Items by Subject

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

Annotations already cover read-only, idempotent, and open-world hints, so the bar is lower. The description adds useful behavioral context beyond the annotations: it returns a paginated list, supports an optional media-type filter, and explicitly lists the return fields (title, creator, date, type, thumbnail, direct URL). This goes beyond what the annotations alone convey.

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?

Three sentences, each earning its place: the first states the core action and scope, the second gives concrete subject examples, and the third covers optional filtering and return payload. No filler or redundant restatement 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?

For a read-only browse tool with 4 parameters (1 required), complete schema descriptions, explicit annotations, and an output schema, the description covers all necessary orientation: what it browses, how subject matching works, optional filtering, pagination existence, and returned fields. Nothing an agent needs to invoke it correctly is missing.

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%, so the baseline is 3. The description's mention of 'subject vocabulary' and 'filter by media type' mirrors what the schema already states for the subject and type parameters. It adds no new semantic details beyond the schema, such as value formats or edge-case behavior, so it stays at the baseline.

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 opens with a specific verb ('Browse'), a clear resource ('digitized items from US archives'), and a precise method ('by subject or topic keyword using DPLA subject vocabulary'). The examples of subjects (Women, Architecture, Civil War) clarify the scope, and the subject-specific focus distinguishes it from the general dpla.archives.search sibling without needing to open 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?

The description implies its intended use case: browsing items categorized by subject vocabulary. However, it never explicitly states when to prefer this over dpla.archives.search or dpla.archives.facets, nor does it mention exclusions or alternatives. The 'by subject' wording gives context, but the guidance is not fully explicit.

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