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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the description's job is to add traits those fields cannot express. It does so concretely: text is truncated past 48,000 characters and metadata.rest points to how to read the remainder, plus it names the companion artifacts returned (citation url and metadata). This is the kind of non-obvious operating constraint that prevents an agent from assuming it received the complete document.

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, front-loaded with the core action and payload description. The parenthetical examples of item kinds are a small cost but earn their place by clarifying what "item" covers; nothing reads as filler.

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?

With a single required parameter, full schema coverage, an output schema, and rich annotations, the remaining burden was operational behavior — truncation and how to continue reading — and the description covers exactly that. Nothing an agent needs in order to call this correctly or interpret the response size 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 coverage is 100% and the single id parameter is already documented as "An id from search." The description reinforces the id's provenance, which slightly increases meaning, but adds no format, example, or validation guidance beyond the schema. Baseline 3 applies when the schema does the heavy lifting.

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 states a specific verb and resource ("Read one item by the id") and scopes the payload ("its full text (the SKILL.md, or the AI tool or mini tool record)"), which implies how it differs from lighter sibling readers like get_item or get_skill. It stops short of naming any sibling explicitly, so an agent must infer the choice between fetch and the various get_* tools from the title's hint of a "deep research shape."

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?

"By the id from search" implies the workflow (search first, then fetch) and gives a usage cue. However, there is no explicit statement of when to prefer this over get_item, get_skill, get_resource, or get_workflow, and no exclusions or preconditions beyond the id's origin.

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