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Glama

Query Layer

query_layer
Read-onlyIdempotent

Query an ArcGIS Feature Service / Map Service layer by its url (from search_datasets). SQL-like where, comma-separated out_fields, order_by, limit, offset. Returns attribute rows (and geometry). Use where="1=1" + out_fields="*" to sample.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
urlYesFeature/Map Service layer url ending in /FeatureServer/<n> or /MapServer/<n>.
limitNoMax features (1-2000, default 50).
whereNoSQL where clause, e.g. "STATE = 'CA' AND YEAR >= 2020". Default "1=1".
offsetNoPagination offset.
order_byNoe.g. "POP DESC".
out_fieldsNoComma-separated field names, or "*" for all (default).

Schema Changelog

Changes observed during successful MCP inspections. Dates show when Glama detected each change.

  1. Changed1 schema field changed
    • addedInput schema / examples
      Added value: +[
      +  {
      +    "limit": 50,
      +    "out_fields": "*",
      +    "url": "https://services.arcgisonline.com/arcgis/rest/services/Montana/FeatureServer/0",
      +    "where": "1=1"
      +  },
      +  {
      +    "limit": 100,
      +    "order_by": "ACRES DESC",
      +    "out_fields": "PARCEL_ID,OWNER,ACRES",
      +    "url": "https://services.arcgisonline.com/arcgis/rest/services/Montana/FeatureServer/1",
      +    "where": "COUNTY = 'Missoula'"
      +  }
      +]
  2. First observed

TDQS

A4.2/5.0
Behavior4/5

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

Annotations already mark it as read-only, idempotent, and non-destructive. The description adds behavioral detail beyond that: it returns attribute rows with geometry, supports SQL-like syntax, and hints at pagination via offset. It doesn't discuss rate limits or errors, but the annotation coverage lowers the burden.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the core purpose, and the second sentence is a valuable tip without redundancy. No wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Despite no output schema, the description states the return type (attribute rows and geometry) and shows how to sample data. Together with the comprehensive parameter schema and strong annotations, the tool is well-specified. Minor gaps like error handling are not critical for a read-only query tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema covers 100% of parameters with clear descriptions, so the description adds little new parameter meaning. It summarizes the parameter names and the SQL-like style, but the schema already provides the full semantic detail. The sampling tip does demonstrate parameter usage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description precisely states the action ('Query') and the resource ('ArcGIS Feature Service / Map Service layer') and notes the URL comes from search_datasets. This distinguishes it from sibling tools like layer_info or search_within.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

It explains the URL comes from search_datasets and provides a concrete example pattern ('where="1=1" + out_fields="*"' to sample). While not explicitly naming alternatives, the sibling context makes it clear this is the querying tool versus metadata/info tools.

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

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TDQS

A3.9/5.0
Disambiguation3/5

Several clusters of similar tools exist: ask_pipeworx, ask_pipeworx_beta (identical right now), and ask_pipeworx_grounded are easily confused, and the many polymarket_* tools overlap heavily. However, the extremely detailed descriptions usually clarify the specific intent, so an agent can often pick correctly.

Naming Consistency4/5

Tool names are uniformly snake_case and mostly follow verb_noun or a recognizable prefix pattern (ask_, polymarket_, pipeworx_). There are a few noun-phrase exceptions like layer_info and entity_profile, but the style is consistent enough that naming is not a major source of confusion.

Tool Count2/5

34 tools is heavy for any server, and especially for one named 'Arcgis Montana' where only three tools (search_datasets, query_layer, layer_info) relate to GIS. Most of the surface is a general-purpose data/analytics API, making the count feel bloated and unfocused.

Completeness2/5

Relative to the implied ArcGIS Montana purpose, the surface is severely incomplete: it only supports searching and querying datasets, with no create/update/delete or administrative capabilities. The Pipeworx functionality is broad, but the GIS side is a thin slice, leaving obvious gaps for geospatial workflows.