Skip to main content
Glama
SmartBear

SmartBear MCP server

Official
by SmartBear

BugSnag: List Spans

bugsnag_list_spans
Read-onlyIdempotent

Retrieve individual spans from a span group with filtering, sorting, and pagination to debug performance issues and analyze slow operations.

Instructions

Get individual spans belonging to a span group

Toolset: Performance

Parameters:

  • projectId (string): Unique identifier of the project. This is optional if a current project is set and is used to set the current project for BugSnag tools.

  • spanGroupId (string) required: ID of the span group

  • sort (enum): Field to sort by

  • direction (enum): Sort direction for ordering results (default: "desc")

  • perPage (number): How many results to return per page. (default: 30)

  • nextUrl (string): URL for retrieving the next page of results. Use the value in the previous response to get the next page when more results are available. Only values provided in the output from this tool can be used. Do not attempt to construct it manually.

  • filters (record<string, array>): Apply filters to narrow down the span group list. Use the List Trace Fields tool to discover available filter fields. Time filters support extended ISO 8601 format (e.g. 2018-05-20T00:00:00Z) or relative format (e.g. 7d, 24h). (default: {"span.since":[{"type":"eq","value":"7d"}]})

Use Cases: 1. Analyze individual slow operations 2. Debug performance issues by examining specific traces 3. Find patterns in operation attributes

Examples:

  1. Get slowest spans for an operation

{
  "spanGroupId": "[HttpClient]GET-api.example.com",
  "sort": "duration",
  "direction": "desc",
  "perPage": 10
}

Expected Output: Array of the 10 slowest span instances

  1. Get spans filtered by OS with pagination

{
  "spanGroupId": "[HttpClient]GET-api.example.com",
  "sort": "timestamp",
  "filters": {
    "os.name": [
      {
        "type": "eq",
        "value": "iOS"
      }
    ]
  },
  "nextUrl": "/projects/123/spans?offset=30&per_page=30"
}

Expected Output: Array of spans from iOS devices with next page navigation

Hints: 1. Sort by duration descending to find the slowest instances 2. Each span includes trace ID for further investigation

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
sortNoField to sort by
filtersNoApply filters to narrow down the span group list. Use the List Trace Fields tool to discover available filter fields. Time filters support extended ISO 8601 format (e.g. 2018-05-20T00:00:00Z) or relative format (e.g. 7d, 24h).
nextUrlNoURL for retrieving the next page of results. Use the value in the previous response to get the next page when more results are available. Only values provided in the output from this tool can be used. Do not attempt to construct it manually.
perPageNoHow many results to return per page.
directionNoSort direction for ordering resultsdesc
projectIdNoUnique identifier of the project. This is optional if a current project is set and is used to set the current project for BugSnag tools.
spanGroupIdYesID of the span group
Behavior4/5

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description's claim of a read operation is consistent. The description adds valuable behavioral details: pagination via nextUrl (with warning not to construct manually), filtering with time format support, and hints for sorting. This goes beyond annotations.

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?

The description is well-organized with clear sections: overview, parameters, use cases, examples, hints. It is front-loaded with the core purpose. No unnecessary sentences; each section earns its place. The examples are practical and illustrate key features like sorting and pagination.

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?

Given the tool's complexity (7 parameters, nested filters, pagination) and no output schema, the description covers essential aspects: parameter defaults, filter field discovery, sorting options, and pagination. It lacks explicit output structure details, but examples implicitly show an array of spans. Hints add further guidance.

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

Parameters4/5

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

Schema coverage is 100%, but the description adds meaningful context: default values for direction and perPage, the format for time filters (ISO 8601 or relative like '7d'), and explicit instructions for nextUrl. The filters parameter's description references the List Trace Fields tool, adding value.

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 title and first sentence clearly state the tool's purpose: 'Get individual spans belonging to a span group.' It distinguishes from siblings like bugsnag_get_span_group (which retrieves the group itself) and bugsnag_list_span_groups (which lists groups).

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

Usage Guidelines3/5

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

The description includes a 'Toolset: Performance' label and lists three use cases (analyze slow operations, debug performance issues, find patterns), giving context. However, it does not explicitly state when to avoid this tool in favor of alternatives like bugsnag_get_trace or bugsnag_list_span_groups, leaving some ambiguity.

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

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/SmartBear/smartbear-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server