metadata_query

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

The readOnlyHint annotation already declares the safety profile, and the description mostly restates it ("Side-effects: None. Read-only metadata query."), which earns no additional credit. It does add scope context ("bounded", "across the active native document") but says nothing about behavior on no matches, on an unknown namespace, or on type mismatches in equals — with annotations carrying safety, a 3 is appropriate.

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?

Three labelled, front-loaded sentences that are easy to scan, with the core purpose first. The middle sentence is largely redundant with the readOnlyHint annotation, which is the only real waste.

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 an output schema present and full parameter coverage, the description need not explain returns or pagination, and it supplies purpose, scope and disambiguation. The remaining gap is conceptual — what a "schema-agnostic metadata namespace" actually contains and what an empty match set means — which is a modest but real shortfall for a niche 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 100%, so path, equals, namespace, limit and offset are already documented in the schema. The description only echoes path and equals semantics and adds nothing about what a namespace key looks like or whether matching is exact/case-sensitive beyond the word "exact". Baseline 3 is correct.

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 (query) and resource (a metadata namespace on the active document) with the matching condition spelled out (one dotted JSON path to an exact JSON value). It is clearly not a write tool, but it never names its closest siblings metadata_get / metadata_set, so the agent must infer the boundary between querying, reading, and writing metadata.

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?

The Disambiguation line gives a concrete selection rule: use this to locate entities by engineering metadata rather than visual layers, which implicitly contrasts with object_query/layer-based tools. It stops short of explicit when-not conditions or naming the metadata_get/metadata_set alternatives for single-key versus multi-entity access.

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