get_material

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

Annotations already declare readOnly, idempotent, open-world, and non-destructive behavior, so the safety profile is covered. The description adds genuinely new behavioral context beyond that: content is returned conditionally for text-bearing items, PDFs require an optional 'pdf extra' to be installed, and folder files are addressed differently — all things the agent cannot infer from 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?

Purpose and conditional return behavior are front-loaded in the first sentence, with parameter format details following. It is dense but free of filler; the parenthetical type list is long yet each element is load-bearing information about what qualifies as text-bearing.

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 need no explanation, and annotations cover safety. The description supplies the remaining essentials — what is fetched, when content accompanies metadata, and the accepted ID forms — though it says nothing about error behavior for invalid IDs or permission requirements, which would complete the picture for an open-world read tool.

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 carry the full burden, and it does: it defines material_id as coming from search_course_materials, accepts a course-module id (cmid), and gives the distinct '<cmid>/<n>' form for folder files. This fully compensates for the undocumented schema field.

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 and resource ('Metadata for one material') and adds a precise scope condition ('plus its content when it is text-bearing') with a concrete list of supported material types. It only indirectly differentiates itself from siblings by naming search_course_materials as the source of material_id, rather than explicitly contrasting the two tools.

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?

Usage is implied: the agent learns that material_id comes from search_course_materials or a cmid, which hints at a search-then-fetch flow, and that content is only returned for text-bearing types. However, there is no explicit when-to-use statement, no exclusions, and no guidance on alternatives if the caller already has a folder path.

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