perf_guidance

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

With no annotations, the description carries the burden. It discloses a limitation: snippets are Zig 0.16-era and advises verifying with zig_std. It also notes principles are universal, implying portability. These are behavioral traits beyond a simple 'getter'. It does not explicitly state it is read-only, but the 'curated guidance' framing implies a non-mutating operation.

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 description is three short sentences, front-loading purpose and then usage. No redundant content; every sentence adds value. It packs routing and caveats efficiently.

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?

Given the tool's simplicity and existing output schema (which covers return format), the description covers usage modes and limitations. It does not specify whether query and topic can be combined, but that is a minor gap. Overall, sufficient for correct invocation.

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 has 0% coverage, so the description must explain parameters. It does: topic=None lists topics, topic='allocation-strategy' returns the guide, query searches across guides. This gives actionable meaning to both params, though it doesn't enumerate all topic values—acceptable because it instructs how to discover them.

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 it provides 'Curated guidance for high-performance lightweight software (Zig-first)', a specific resource type. It distinguishes from siblings like zig_std (API reference) and zig_search (search) by focusing on performance guidance. The usage examples (topic listing, specific topic retrieval, query search) further clarify its role.

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?

Explicitly explains how to use without params (topic=None lists topics), with a specific topic (topic='allocation-strategy' returns the guide), and with query (searches across all guides). It also points to zig_std for API verification, indicating when not to rely on this tool for exact APIs. This is clear routing to an alternative.

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