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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds genuine value by disclosing data vintage/quality traits: 'period, scale and missing-data status', and by clarifying the data is observational, not live.

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?

Two dense sentences, front-loaded with the data payload and ending with the scope disclaimer; nothing is wasted. The opening is a noun-phrase fragment rather than a verb-led statement, which slightly weakens front-loading.

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?

An output schema exists, so return structure need not be explained, and the description still surfaces the key interpretive fields (period, scale, missing-data status). For a read-only, two-parameter tool with clear scope exclusions, only the missing street_id acquisition path leaves a gap.

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 0%, so the description must carry the parameter burden. It effectively names the three dimensions (walkability, SNAP retailers, EV stations) matching the enum values, but says nothing about street_id format (the us:#### pattern) or how the dimensions array is selected/combined.

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 names the specific resource and its content: EPA block-group walkability plus observed SNAP retailer and EV station counts near the street centroid. That is concrete enough to distinguish it from the search/compare siblings, though it never names an alternative tool explicitly.

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 the data scoping, and the closing clause 'Not a home, safety or live availability assessment' usefully bounds what the tool should not be used for. However it gives no positive routing guidance, e.g. that search_streets should be used first to obtain a street_id, so an agent must infer the workflow.

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