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

With no annotations provided, the description carries the full burden and does well: it discloses that pricing-intent boilerplate is stripped before matching, that match_certainty is 'confident' vs 'uncertain', that pricing is WITHHELD when nothing is close, and that the tool returns status no_match or thin_coverage with a next_step. It also states 'Read-only.' A small gap: it doesn't detail rate limits or auth, but for a read-only mapping tool the behavioral disclosure is strong.

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 dense but every sentence earns its place: it defines the core behavior, the audience, the matching mechanism, the return fields, the certainty semantics, the alternative tool, and the failure modes. It is front-loaded with the primary purpose and scoping. It is long, but the length is justified by the tool's complexity and the absence of annotations and output schema.

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 complexity, the lack of annotations, and the absence of an output schema, the description is remarkably complete: it names the return fields (market label, provider counts, nearest, pricing_by_tier with tier names), explains match_certainty, and describes the no_match/thin_coverage statuses. It doesn't spell out the exact JSON shape of `nearest` or `pricing_by_tier`, but it provides enough for an agent to invoke the tool and interpret the result.

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 adds meaning beyond the schema by explaining that `task` accepts natural-language plain words, gives an example ('reconcile supplier invoices'), notes that an empty call returns needs_input, and clarifies that `query` is a back-compat alias. This is useful semantic context that helps an agent construct a valid call.

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 opens with a specific verb ('Map') and a precise resource ('a natural-language task, capability or service to its live MARKET'), then defines the market as a semantic neighbourhood found by text-embedding nearness with no fixed category. It clearly distinguishes itself from siblings like research_capability and search_providers by naming them and stating the one-call alternative.

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 description explicitly states when to use this tool: for buyers, sellers, or sizing a space, and names the alternative research_capability for a full market read plus shortlist in one call. It also explains the no_match/thin_coverage behavior and that it never invents a market, which helps an agent decide when this tool is appropriate.

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