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

Annotations already cover the safety profile (readOnly, idempotent, closed-world), so the description's job is to add context 'be' that. It does: it discloses the returned payload shape and ordering (rust first, then astro, then react), the `lead` fallback rule when no Rust exists, and legacy name resolution. It omits error/not-found behavior, which keeps it short of a 5.

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?

The key fact is front-loaded, which is good, but the prose is dense and sprawling, with very long parenthetical sentences mixing roadmap trivia (Dioxus 0.7 migration, registry issue numbers #397) that does not help an agent select or invoke the tool. It is informative but not tightly edited.

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 no output schema and full annotation coverage, the description commendably documents the return structure, the `lead` field, and the include-driven extras. The remaining gap is failure mode — what happens when `name` doesn't resolve — which leaves the agent without guidance on the unhappy path.

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%, so the baseline is 3. The description goes beyond it by explaining what `include: docs|versions` actually retrieves (use cases, variants, a11y contract, changelog) and where it appears, and by noting that former nyuchi-* names resolve to mzizi-* successors — a naming semantic the schema does not capture.

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?

Opens with a specific verb+resource+scope: 'Fetch one component in full.' The word 'one' implicitly separates it from the sibling mzizi_list_components, and the rest of the text spells out exactly what 'in full' means (rust/astro/react payloads, lead, contract, source). An agent knows precisely what this returns without opening 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?

Usage is implied by 'Fetch one component in full' versus the listing sibling, and the `include` sentence implies when to opt into docs/versions. However, there is no explicit when-to-use/when-not statement or named alternative (e.g. list_components, search, get_tokens), so the agent must infer routing from the purpose sentence alone.

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