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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is fully covered structurally. The description adds one genuinely useful behavioral fact — 'No API key' — but says nothing about response shape, size of the category list, or caching. With annotations doing most of the work, this is a modest addition.

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 short sentences, each earning its place: what it returns, where the output goes, and the auth constraint. Front-loaded with the action and resource.

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?

For a zero-parameter, no-output-schema lookup tool, the description covers what comes back (ids and titles), how to use the result, and the auth requirement. Nothing an agent needs in order to call it correctly is missing.

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?

Zero parameters, so the baseline is 4; the description correctly implies no input is needed and instead directs the returned values onward to eonet_events. There is no parameter ambiguity to resolve.

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 and resource ('List NASA EONET v3 category ids and titles'), making it immediately distinguishable from the event-oriented siblings like eonet_events and fires_near. An agent knows this is the taxonomy/lookup endpoint without opening anything else.

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?

'Pass a category id to eonet_events' explicitly names the downstream consumer and the workflow, which is strong routing guidance. It stops short of stating when not to call this (e.g., if the agent already knows the category id), so it lacks an explicit exclusion.

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

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

Annotations already cover readOnly, idempotent, openWorld and non-destructive, so the bar is lower. The description still adds two things the annotations don't: 'No API key' (an auth prerequisite) and 'Not for safety-of-life decisions' (a data-reliability caveat), which meaningfully shapes how an agent should present results.

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 short clauses, front-loaded with the core action and with zero filler. Every sentence (what it returns, auth requirement, disclaimer) 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 does the necessary work by naming the returned sections (categories, sources, geometries). Minor gaps remain around error behavior for a malformed or unknown id, but nothing blocks a correct call.

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?

There is a single required parameter with 0% schema description coverage; the schema only supplies a regex pattern. The description says 'by id', which confirms what the parameter is, but adds nothing about where an id comes from or what an invalid id produces.

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+resource: fetch one NASA EONET v3 event by id, and lists the payload sections returned (categories, sources, geometries). The singular 'one event by id' implicitly separates it from the sibling list tool eonet_events, though the sibling is never named.

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 only implied by the 'by id' framing — an agent can infer this is the lookup path once an id is known from eonet_events or nearby_hazards, but no alternative is named and no when-not-to-use condition is given. The safety caveat is a disclaimer, not selection guidance.

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

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

Annotations already cover read-only, idempotent, open-world and non-destructive behavior, and the description adds useful context beyond them: no API key required, third-party source licensing caveats, and a safety disclaimer. It doesn't disclose pagination behavior or result-set semantics for the limit parameter, which keeps it below 5.

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?

Four dense sentences with no filler, front-loaded with the resource and followed by filters, operational notes, and the safety caveat in descending order of importance. Every sentence earns its place.

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?

For a 9-optional-parameter tool with no output schema, the description should say something about the shape of returned events (list vs. single, geometry fields) and pagination behavior; it only says events link to third-party sources. Adequate for calling the tool, but incomplete for interpreting results.

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?

With 0% schema description coverage, the description must carry parameter meaning, and it names all 9: category id, status values (open/closed/all), date format YYYY-MM-DD, limit, and the west/south/east/north bbox. It doesn't state defaults (status=open, limit=20) or ranges (1-100, ±180/±90), but those constraints are visible in the schema, so the semantic gap is mostly filled.

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+resource: listing natural-event metadata from NASA EONET v3. It's clearly distinguishable from eonet_categories or fires_* siblings, but it never says how it differs from the singular eonet_event sibling, leaving a small ambiguity about list vs. single-record retrieval.

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 filter enumeration implies the intended usage (query events by category/status/date/bbox) and 'Not for safety-of-life decisions' provides a genuine when-not exclusion. However, there's no explicit when-to-use guidance relative to eonet_event or nearby_hazards, so the agent must infer routing.

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

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

Annotations already declare readOnly/idempotent/openWorld, and the description adds genuinely non-redundant behavior: the upstream country endpoint is flagged unavailable and the tool surfaces the failure, an API key is required, and it is explicitly not for safety-of-life use. These are meaningful operational facts an agent needs; only the return/error shape is left unstated.

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?

Four tight sentences with the resource scope front-loaded and the critical unavailability warning prominent. Every sentence carries information; no filler, though the guidance could be marginally more organized.

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?

Covers the operational essentials (key requirement, current outage, non-safety-of-life caveat) but, with 0% schema coverage and no output schema, omits the meaning of the source enum and date parameter that an agent needs to call it correctly.

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 parameter meaning, yet it only addresses country (ISO alpha-3) and day_range (1-5). It says nothing about the date format or the 8-value source enum, leaving half the parameters undocumented anywhere.

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 (active fire hotspots from NASA FIRMS) scoped to a single ISO alpha-3 country, which implicitly distinguishes it from the nearby-geography sibling fires_near. Clear enough to select without opening the schema, though the contrast with fires_near is only implied.

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?

Provides useful constraints (day_range 1-5, requires FIRMS_MAP_KEY) and an important warning that the upstream endpoint is currently unavailable, but never names when to use this instead of fires_near or nearby_hazards. Usage is implied by scope rather than explicit routing.

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

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

Annotations already cover the safety profile (readOnly, idempotent, openWorld, non-destructive), so the bar is lower, and the description adds real operational context: it requires FIRMS_MAP_KEY, results are ordered nearest-first, Suomi-NPP deliveries stop 2026-11-02, and it is 'Not for safety-of-life decisions.' It does not say what a hotspot record contains, which is the main remaining gap.

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?

Front-loaded with purpose, then parameter mechanics, then operational caveats — a sensible ordering with essentially no filler sentences. Minor waste in restating schema constraints verbatim ('greater than 0 and at most 2500', 'integer from 1 to 5').

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?

For a 10-parameter, no-output-schema tool this covers the essentials an agent needs to call it correctly: auth requirement, mode selection, ordering, source default and deprecation, and a suitability caveat. It omits the date filter and gives no hint of the response shape, which for a tool with no output schema is a notable but not disqualifying 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 carries the burden and mostly does: it explains both coordinate groups, radius_km units and bounds, day_range's 1-5 range, and source's default plus a deprecation note. The 'date' parameter (YYYY-MM-DD) is never mentioned in the description and is only inferable from the schema pattern, and the source enum values are not characterized.

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 resource with provenance ('Active fire hotspots from NASA FIRMS') and immediately defines the two query geometries (point radius vs. bounding box), which implicitly separates it from the country-scoped sibling fires_by_country. It stops short of naming any sibling explicitly, so an agent must infer the routing.

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 gives clear invocation guidance for two modes ('Pass latitude, longitude, and radius_km ... or west, south, east, and north') and explains point-query behavior, but never says when to prefer this over fires_by_country, nearby_hazards, or eonet_events. Usage is implied by parameter shape rather than stated.

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

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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so the safety profile is covered. The description adds real behavioral context beyond that: graceful degradation when FIRMS_MAP_KEY is unset or FIRMS fails, with a firms_note explaining why, plus the fact that limit caps both result sets and hotspots are returned nearest-first. It does not describe result ordering for events or response shape, keeping it at 4.

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?

Front-loaded with the core purpose and tight overall, with every clause carrying operational meaning except 'day_range is 1 to 5', which merely restates the schema's minimum and maximum. Minor redundancy, but the ordering is sensible and there is no filler prose.

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?

There is no output schema and no annotations-led return description beyond the mention of firms_note. For a tool that merges two heterogeneous sources (EONET events vs FIRMS hotspots) with six parameters, the description should say something about what each source's records look like or how to tell them apart in the response. Adequate for calling, incomplete for interpreting results.

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 parameter meaning. It clarifies limit's dual capping behavior and day_range's 1-5 window, and latitude/longitude/radius_km are self-evident from naming. The source parameter with its eight-item VIIRS/MODIS/LANDSAT enum is left entirely unexplained — the single most consequential omission for a caller choosing a satellite dataset.

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-and-resource statement: 'Open EONET events and FIRMS hotspots within radius_km of a latitude and longitude.' That makes the combined-source nature clear enough that an agent can distinguish it from single-source siblings like fires_near and eonet_events. It stops short of explicitly naming the siblings as alternatives, so a 5 is not warranted.

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?

Provides a genuine exclusion ('Not for safety-of-life decisions') and explains the FIRMS fallback, which is useful usage context. However, it never states when to prefer this tool over sibling tools such as fires_near or eonet_events, nor any prerequisites such as FIRMS_MAP_KEY being needed up front. Usage is implied rather than directed.

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