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

Annotations declare readOnlyHint and openWorldHint, so safety is covered; the description adds real behavioral context beyond that: answers are grounded only in the project record, every line is tagged FACT/DERIVED/UNKNOWN with its source, and coverage is limited to building with no view on price. It does not discuss limits, failure modes, or latency.

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 tight sentences with zero filler: scope first, then grounding and output tagging, then the two hard constraints. Front-loaded and each sentence carries distinct information.

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, the description carries the return-format burden and does so by explaining the FACT/DERIVED/UNKNOWN tagging. Scope constraints (one project, building only, no price) round it out. An agent has enough to invoke correctly, though sibling routing remains unaddressed.

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% with only two required params (slug, question), so the schema already does the heavy lifting. The description adds only the language allowance (English or Malay) and confirms single-project scope; the 280-char cap and slug format live in the schema.

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 concrete verb+resource: HEY answers a free-text question about one project's record. The grounding rule ('answers only from that record') is specific. It does not explicitly distinguish itself from siblings like explain_fact or get_evidence, 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?

Usage is implied — use it when you have a natural-language question about a single project, not a structured lookup. There is no explicit when-not guidance or pointer to the sibling tools (explain_fact, get_evidence, get_contract) that handle fact-level or evidence-level queries.

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