fetch_articles

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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false and destructiveHint=true, so the safety profile is covered. The description adds the useful source-fallback behavior and the batching loop, but never explains why the operation is destructive or what state it mutates, which is the one thing the annotations flag as risky.

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 compact sentences, front-loaded with the action and the source fallback, with the loop condition stated before the pointer. The trailing 'Rules: guide("fetch")' is terse to the point of being cryptic, keeping it from a 5.

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 not be described, and the core fetch loop plus fallback order are covered. Missing is any explanation of the destructive/mutating nature flagged by annotations and the external-API failure/rate-limit behavior implied by openWorldHint, leaving a meaningful gap for a batch 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 coverage is 80%, so the schema documents uids, run_id, max_items and the two retry flags on its own. The description only reinforces that the default target is 'included articles', adding little beyond the schema's 'next pending ones' note; the baseline 3 applies.

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 ('Fetch full text of included articles') and adds the source hierarchy (PMC, Unpaywall open access, else abstract), which tells the agent exactly what content it will get. It does not explicitly distinguish itself from siblings like get_article_page or list_articles, so it stops short of a 5.

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?

'repeat while remaining > 0' gives a clear operational loop, which is genuine usage guidance. However, it defers all detailed rules to guide("fetch") rather than stating them, and there is no when-not-to-use or explicit alternative (e.g. get_article_page).

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